Streaming service data receiving device and method in mobile communication system for supporting plurality of radio access interfaces

ABSTRACT

The present invention relates to technology for a sensor network, machine to machine (M2M) communication, machine type communication (MTC), and the Internet of things (IoT). The present invention can be utilized for intelligent services (smart home, smart building, smart city, smart car or connected car, health care, digital education, retail business, security and safety-related services, and the like) based on the technology. The present invention relates to a streaming service data receiving method of a terminal in a mobile communication system for supporting a plurality of radio access interfaces, the method comprising a step of receiving streaming service data from a server through at least one of the plurality of radio access interfaces, wherein the at least one radio access interface is selected such that the streaming service data can be received at a network speed corresponding to an encoding bit rate to be applied to the streaming service.

CROSS-REFERENCE TO RELATED APPLICATION(S)

This application is a U.S. National Stage application under 35 U.S.C.§371 of an International application filed on Sep. 30, 2015 and assignedapplication number PCT/KR2015/010275, which claimed the benefit of aKorean patent application filed on Sep. 30, 2014 in the KoreanIntellectual Property Office and assigned Serial number 10-2014-0131856,the entire disclosure of which is hereby incorporated by reference.

TECHNICAL FIELD

The present disclosure relates to a streaming service data receivingapparatus and method in a mobile communication system, and moreparticularly, to an apparatus and method for receiving streaming servicedata in a mobile communication system supporting a plurality of radioaccess interfaces.

BACKGROUND

The Internet, which is a human centered connectivity network wherehumans generate and consume information, is now evolving to the internetof things (IoT) where distributed entities, such as things, exchange andprocess information without human intervention. The internet ofeverything (IoE), which is a combination of the IoT technology and thebig data processing technology through connection with a cloud server,has emerged.

As technology elements, such as “sensing technology”, “wired/wirelesscommunication and network infrastructure”, “service interfacetechnology”, and “security technology” have been demanded for IoTimplementation, a sensor network, a machine-to-machine (M2M)communication, machine type communication (MTC), and so forth have beenrecently researched. Such an IoT environment may provide intelligentInternet technology services that create a new value to human life bycollecting and analyzing data generated among connected things. IoT maybe applied to a variety of fields including smart home, smart building,smart city, smart car or connected cars, smart grid, health care, smartappliances and advanced medical services through convergence andcombination between existing information technology (IT) and variousindustrial applications.

Mobile communication systems have been rapidly progressed, and smartphones have been populated, so use of mobile data has been rapidlyincreased. In particular, a streaming service such as video trafficaccounts for the highest percentage among mobile traffic, it will bepredicted that video traffic accounts for 66% of total mobile traffic in2014 according to a Cisco Visual Networking Index data.

Meanwhile, examples of a video streaming service which has been widelyused in a mobile communication system are a service provided at aYouTube site and a service provided at a Netflix site. The YouTube siteand the Netflix site provide a streaming service, e.g., a videostreaming service which is based on a Hypertext Transfer Protocol(HTTP). Here, a reason why the video streaming service which is based onthe HTTP is preferable compared to an existing video streaming protocolwill be described below.

The first reason is that the video streaming service which is based onthe HTTP is less expensive than the existing video streaming protocol.The video streaming service which is based on the HTTP is the same as acase of downloading data using an HTTP data. So, the video streamingservice which is based on the HTTP does not request a specific protocolfrom a station, and a server needs to provide only a WEB service.

The second reason is that it is easy for the video streaming servicewhich is based on the HTTP to pass a firewall compared to the existingvideo streaming protocol. A plurality of sites which have been currentlyprovided have been blocked by a firewall except for well-known ports.Existing video streaming protocols use a specific port using a UserDatagram Protocol (UDP), so there is a high probability that theexisting video streaming protocols will be finally blocked by thefirewall. On the contrary, the video streaming service which is based onthe HTTP uses a well-known 80 port, so there is an advantage that thevideo streaming service which is based on the HTTP may easily pass thefirewall.

The fourth reason is that a proxy server or a cache server has beenwidely used for reducing load of a server or fast data transmission, itis relatively easy to use the proxy server or the cache server sincethere is a need for only a simple WEB server for providing the videostreaming service which is based on the HTTP.

Meanwhile, a currently the most used video streaming protocol which isbased on an HTTP includes an HTTP Progressive Download (PL) protocol andan HTTP Adaptive Streaming (AS) protocol. Compared to a general HTTPprotocol, the HTTP PL protocol and the HTTP AS protocol are similar tothe general HTTP protocol except that the HTTP PL protocol and the HTTPAS protocol report a communication state of a station to a server toprovide a Quality of Service (QoS).

Meanwhile, a station has been progressed according to progress of amobile communication system. Recently, one station is capable ofsupporting a plurality of radio access interfaces. For example, astation may support total two radio access interfaces including awireless fidelity (Wi-Fi) interface and a long term evolution-advanced(LTE) interface.

However, in a mobile communication system which has been proposed up tonow, even though a station supports a plurality of radio accessinterfaces, a streaming service is provided to the station through oneof the plurality of radio access interfaces at corresponding time. So,it is inevitable that a streaming service is provided to the stationthrough a limited radio access interface at a limited network speed, soa break phenomenon may occur when the streaming service is played, andthis finally results in service quality degradation.

So, there is a need for a scheme of seamlessly receiving streamingservice data in a mobile communication system.

More particularly, in a case of a video streaming service, it isimportant that a station receives video streaming service data at anetwork speed which corresponds to an encoding bit rate applied to videocontent in a server. However, in a mobile communication system proposedup to now, there is no detailed scheme of receiving video streamingservice data at a network speed which corresponds to an encoding bitrate applied to video content in a server.

So, there is a need for a scheme of receiving video streaming servicedata corresponding to an encoding bit rate applied to streaming servicecontent in a mobile communication system.

The above information is presented as background information only toassist with an understanding of the present disclosure. No determinationhas been made, and no assertion is made, as to whether any of the abovemight be applicable as prior art with regard to the present disclosure.

SUMMARY

An embodiment of the present disclosure proposes an apparatus and methodfor receiving streaming service data in a mobile communication systemsupporting a plurality of radio access interfaces.

An embodiment of the present disclosure proposes an apparatus and methodfor seamlessly receiving streaming service data in a mobilecommunication system supporting a plurality of radio access interfaces.

An embodiment of the present disclosure proposes an apparatus and methodfor receiving streaming service data corresponding to an encoding bitrate applied to streaming service content in a mobile communicationsystem supporting a plurality of radio access interfaces.

An embodiment of the present disclosure proposes an apparatus and methodfor receiving streaming service data by considering load balancing in amobile communication system supporting a plurality of radio accessinterfaces.

An embodiment of the present disclosure proposes an apparatus and methodfor receiving streaming service data such that high-definition videocontent may be played from playback start time in a mobile communicationsystem supporting a plurality of radio access interfaces according to anembodiment of the present disclosure.

An embodiment of the present disclosure proposes an apparatus and methodfor receiving streaming service data by considering guarantee ofstability in a mobile communication system supporting a plurality ofradio access interfaces.

In accordance with an aspect of the present disclosure, a method forreceiving streaming service data of a station in a mobile communicationsystem supporting a plurality of radio access interfaces is provided.The method includes receiving streaming service data from a serverthrough at least one of a plurality of radio access interfaces, whereinthe at least one of the plurality of radio access interfaces is selectedsuch that the streaming service data may be received at a network speedwhich corresponds to an encoding bit rate applied to the streamingservice.

In accordance with another aspect of the present disclosure, a stationin a mobile communication system supporting a plurality of radio accessinterfaces is provided. The station includes a receiver for receivingstreaming service data from a server through at least one of a pluralityof radio access interfaces, wherein the at least one of the plurality ofradio access interfaces is selected such that the streaming service datamay be received at a network speed which corresponds to an encoding bitrate applied to the streaming service.

Other aspects, advantages, and salient features of the disclosure willbecome apparent to those skilled in the art from the following detaileddescription, which, taken in conjunction with the annexed drawings,discloses exemplary embodiments of the disclosure.

Before undertaking the DETAILED DESCRIPTION below, it may beadvantageous to set forth definitions of certain words and phrases usedthroughout this patent document: the terms “include” and “comprise,” aswell as derivatives thereof, mean inclusion without limitation; the term“or,” is inclusive, meaning and/or; the phrases “associated with” and“associated therewith,” as well as derivatives thereof, may mean toinclude, be included within, interconnect with, contain, be containedwithin, connect to or with, couple to or with, be communicable with,cooperate with, interleave, juxtapose, be proximate to, be bound to orwith, have, have a property of, or the like; and the term “controller”means any device, system or part thereof that controls at least oneoperation, such a device may be implemented in hardware, firmware orsoftware, or some combination of at least two of the same. It should benoted that the functionality associated with any particular controllermay be centralized or distributed, whether locally or remotely.Definitions for certain words and phrases are provided throughout thispatent document, those of ordinary skill in the art should understandthat in many, if not most instances, such definitions apply to prior, aswell as future uses of such defined words and phrases.

BRIEF DESCRIPTION OF THE DRAWINGS

The above and other aspects, features and advantages of certainexemplary embodiments of the present disclosure will be more apparentfrom the following description taken in conjunction with theaccompanying drawings, in which:

FIG. 1 schematically illustrates an example of a format of streamingservice content in a communication system supporting a plurality ofradio access interfaces according to an embodiment of the presentdisclosure;

FIG. 2 schematically illustrates another example of a format ofstreaming service content in a communication system supporting aplurality of radio access interfaces according to an embodiment of thepresent disclosure;

FIG. 3 schematically illustrates a fast pre-fetching process for astreaming service in a communication system supporting a plurality ofradio access interfaces according to an embodiment of the presentdisclosure;

FIG. 4 schematically illustrates an example of a load balancing processfor a streaming service in a communication system supporting a pluralityof radio access interfaces according to an embodiment of the presentdisclosure;

FIG. 5 schematically illustrates another example of a load balancingprocess for a streaming service in a communication system supporting aplurality of radio access interfaces according to an embodiment of thepresent disclosure;

FIG. 6 schematically illustrates an example of detailed implementationof a load balancing process for a streaming service in a communicationsystem supporting a plurality of radio access interfaces according to anembodiment of the present disclosure;

FIG. 7 schematically illustrates relation between a network speed anddownload time according to detailed implementation of a load balancingprocess for a streaming service in a communication system supporting aplurality of radio access interfaces as shown in FIG. 6;

FIG. 8 schematically illustrates an example of a stability guaranteeingprocess for a streaming service in a communication system supporting aplurality of radio access interfaces according to an embodiment of thepresent disclosure;

FIG. 9 schematically illustrates another example of a stabilityguaranteeing process for a streaming service in a communication systemsupporting a plurality of radio access interfaces according to anembodiment of the present disclosure;

FIG. 10 schematically illustrates still another example of a stabilityguaranteeing process for a streaming service in a communication systemsupporting a plurality of radio access interfaces according to anembodiment of the present disclosure;

FIG. 11 schematically illustrates relation among a network speed andradio access interfaces according to still another example of astability guaranteeing process for a streaming service in acommunication system supporting a plurality of radio access interfacesas shown in FIG. 10;

FIG. 12 schematically illustrates still another example of a stabilityguaranteeing process for a streaming service in a communication systemsupporting a plurality of radio access interfaces according to anembodiment of the present disclosure;

FIG. 13 schematically illustrates still another example of a stabilityguaranteeing process for a streaming service in a communication systemsupporting a plurality of radio access interfaces according to anembodiment of the present disclosure;

FIG. 14 schematically illustrates still another example of a stabilityguaranteeing process for a streaming service in a communication systemsupporting a plurality of radio access interfaces according to anembodiment of the present disclosure;

FIG. 15 schematically illustrates a process of receiving streamingservice data in a case that an HTTP AS protocol is used in acommunication system supporting a plurality of radio access interfacesaccording to an embodiment of the present disclosure;

FIGS. 16a and 16b schematically illustrate a process of receivingstreaming service data such that high-definition video content may beplayed from playback start time in a mobile communication systemsupporting a plurality of radio access interfaces according to anembodiment of the present disclosure;

FIG. 17 schematically illustrates a process of measuring a bandwidthshown in step 1617 in FIG. 16 a;

FIG. 18 schematically illustrates an inner structure of a server in acommunication system supporting a plurality of radio access interfacesaccording to an embodiment of the present disclosure;

FIG. 19 schematically illustrates an inner structure of a station in acommunication system supporting a plurality of radio access interfacesaccording to an embodiment of the present disclosure;

FIG. 20 schematically illustrates an inner structure of a transmitter1911 in FIG. 19; and

FIG. 21 schematically illustrates an inner structure of a receiver 1915in FIG. 19.

Throughout the drawings, it should be noted that like reference numbersare used to depict the same or similar elements, features, andstructures.

DETAILED DESCRIPTION

The following description with reference to the accompanying drawings isprovided to assist in a comprehensive understanding of variousembodiments of the present disclosure as defined by the claims and theirequivalents. It includes various specific details to assist in thatunderstanding but these are to be regarded as merely exemplary.Accordingly, those of ordinary skill in the art will recognize thatvarious changes and modifications of the various embodiments describedherein can be made without departing from the scope and spirit of thepresent disclosure. In addition, descriptions of well-known functionsand constructions may be omitted for clarity and conciseness.

The terms and words used in the following description and claims are notlimited to the bibliographical meanings, but, are merely used by theinventor to enable a clear and consistent understanding of the presentdisclosure. Accordingly, it should be apparent to those skilled in theart that the following description of various embodiments of the presentdisclosure is provided for illustration purpose only and not for thepurpose of limiting the present disclosure as defined by the appendedclaims and their equivalents.

It is to be understood that the singular forms “a,” “an,” and “the”include plural referents unless the context clearly dictates otherwise.Thus, for example, reference to “a component surface” includes referenceto one or more of such surfaces.

Although ordinal numbers such as “first,” “second,” and so forth will beused to describe various components, those components are not limitedherein. The terms are used only for distinguishing one component fromanother component. For example, a first component may be referred to asa second component and likewise, a second component may also be referredto as a first component, without departing from the teaching of theinventive concept. The term “and/or” used herein includes any and allcombinations of one or more of the associated listed items.

The terminology used herein is for the purpose of describing variousembodiments only and is not intended to be limiting. As used herein, thesingular forms are intended to include the plural forms as well, unlessthe context clearly indicates otherwise. It will be further understoodthat the terms “comprises” and/or “has,” when used in thisspecification, specify the presence of a stated feature, number, step,operation, component, element, or combination thereof, but do notpreclude the presence or addition of one or more other features,numbers, steps, operations, components, elements, or combinationsthereof.

The terms used herein, including technical and scientific terms, havethe same meanings as terms that are generally understood by thoseskilled in the art, as long as the terms are not differently defined. Itshould be understood that terms defined in a generally-used dictionaryhave meanings coinciding with those of terms in the related technology.

According to various embodiments of the present disclosure, anelectronic device may include communication functionality. For example,an electronic device may be a smart phone, a tablet personal computer(PC), a mobile phone, a video phone, an e-book reader, a desktop PC, alaptop PC, a netbook PC, a personal digital assistant (PDA), a portablemultimedia player (PMP), an mp3 player, a mobile medical device, acamera, a wearable device (e.g., a head-mounted device (HMD), electronicclothes, electronic braces, an electronic necklace, an electronicappcessory, an electronic tattoo, or a smart watch), and/or the like.

According to various embodiments of the present disclosure, anelectronic device may be a smart home appliance with communicationfunctionality. A smart home appliance may be, for example, a television,a digital video disk (DVD) player, an audio, a refrigerator, an airconditioner, a vacuum cleaner, an oven, a microwave oven, a washer, adryer, an air purifier, a set-top box, a TV box (e.g., SamsungHomeSync™, Apple TV™, or Google TV™), a gaming console, an electronicdictionary, an electronic key, a camcorder, an electronic picture frame,and/or the like.

According to various embodiments of the present disclosure, anelectronic device may be a medical device (e.g., magnetic resonanceangiography (MRA) device, a magnetic resonance imaging (MRI) device,computed tomography (CT) device, an imaging device, or an ultrasonicdevice), a navigation device, a global positioning system (GPS)receiver, an event data recorder (EDR), a flight data recorder (FDR), anautomotive infotainment device, a naval electronic device (e.g., navalnavigation device, gyroscope, or compass), an avionic electronic device,a security device, an industrial or consumer robot, and/or the like.

According to various embodiments of the present disclosure, anelectronic device may be furniture, part of a building/structure, anelectronic board, electronic signature receiving device, a projector,various measuring devices (e.g., water, electricity, gas orelectro-magnetic wave measuring devices), and/or the like that includecommunication functionality.

According to various embodiments of the present disclosure, anelectronic device may be any combination of the foregoing devices. Inaddition, it will be apparent to one having ordinary skill in the artthat an electronic device according to various embodiments of thepresent disclosure is not limited to the foregoing devices.

According to various embodiments of the present disclosure, for example,a station may be an electronic device.

According to various embodiments of the present disclosure, a stationoperates as, for example, a receiving apparatus of receiving streamingservice data, and a server operates as, for example, a transmittingapparatus of transmitting streaming service data.

An embodiment of the present disclosure proposes an apparatus and methodfor receiving streaming service data in a mobile communication systemsupporting a plurality of radio access interfaces.

An embodiment of the present disclosure proposes an apparatus and methodfor seamlessly receiving streaming service data in a mobilecommunication system supporting a plurality of radio access interfaces.

An embodiment of the present disclosure proposes an apparatus and methodfor receiving streaming service data corresponding to an encoding bitrate applied to streaming service content in a mobile communicationsystem supporting a plurality of radio access interfaces.

An embodiment of the present disclosure proposes an apparatus and methodfor receiving streaming service data by considering load balancing in amobile communication system supporting a plurality of radio accessinterfaces.

An embodiment of the present disclosure proposes an apparatus and methodfor receiving streaming service data such that high-definition videocontent may be played high-definition video content from playback starttime in a mobile communication system supporting a plurality of radioaccess interfaces.

An embodiment of the present disclosure proposes an apparatus and methodfor receiving streaming service data by considering guarantee ofstability in a mobile communication system supporting a plurality ofradio access interfaces.

An apparatus and method proposed in various embodiments of the presentdisclosure may be applied to various communication systems such as aninstitute of electrical and electronics engineers (IEEE) 802.11accommunication system, an IEEE 802.16 communication system, a digitalvideo broadcast system such as a mobile broadcast service such as adigital multimedia broadcasting (DMB) service, a digital videobroadcasting-handheld (DVP-H), an advanced television systemscommittee-mobile/handheld (ATSC-M/H) service, and the like, and aninternet protocol television (IPTV), a moving picture experts group(MPEG) media transport (MMT) system, an evolved packet system (EPS), along term evolution (LTE) mobile communication system, an LTE-advanced(LTE-A) mobile communication system, a high speed downlink packet access(HSDPA) mobile communication system, a high speed uplink packet access(HSUPA) mobile communication system, a high rate packet data (HRPD)mobile communication system proposed in a 3^(rd) generation projectpartnership 2 (3GPP2), a wideband code division multiple access (WCDMA)mobile communication system proposed in the 3GPP2, a code divisionmultiple access (CDMA) mobile communication system proposed in the3GPP2, a mobile internet protocol (Mobile IP) system, and/or the like.

Firstly, terminologies used in various embodiments of the presentdisclosure will be described below.

(1) Segment

A segment denotes a part of streaming service content, e.g., videocontent, and the streaming service content includes at least onesegment.

If a streaming service is downloaded using a Hypertext Transfer Protocol(HTTP) Progressive Download (PL) protocol and an HTTP Adaptive Streaming(AS) protocol which are based on an HTTP, a size of the segment may bedetermined as the following.

Firstly, in a case that the streaming service is downloaded using anHTTP PL protocol, an entity fragmenting/merging streaming service dataautonomously determines a segment size of a fixed/variable size in orderfor a station to use a plurality of radio access interfaces. Forexample, if the streaming service is downloaded using the HTTP PLprotocol, a segment size may be determined as 10 MB. Alternatively, thesegment size may be determined as a bit rate of a streaming service *segment time.

Secondly, if the streaming service is downloaded using an HTTP ASprotocol, a basic unit to which encoding is applied based on a pluralityof bit rates is the segment. In this case, a segment size is determinedin an application layer.

(2) Chunk

If a plurality of radio access interfaces are used at the same time, achunk denotes a range or amount of streaming service data which isintended to receive through each of the plurality of radio accessinterfaces. The chunk is a part of the segment, and one segment includesat least one chunk.

If one segment includes a plurality of chunks, and the plurality ofradio access interfaces are used at the same time, each of the pluralityof chunks will be received through each of the plurality of radio accessinterfaces, or the plurality of chunks will be received through one ofthe plurality of radio access interfaces, or the plurality of chunkswill be received through a part of the plurality of radio accessinterfaces.

Exceptionally, if a size of a segment is less than a threshold segmentsize, a plurality of segments may be configured as one chunk. Here, thethreshold segment size may be determined appropriate to a situation of amobile communication system, and an operation of determining thethreshold segment size will be omitted herein.

An example of a format of streaming service content in a communicationsystem supporting a plurality of radio access interfaces according to anembodiment of the present disclosure will be described with reference toFIG. 1.

FIG. 1 schematically illustrates an example of a format of streamingservice content in a communication system supporting a plurality ofradio access interfaces according to an embodiment of the presentdisclosure.

Referring to FIG. 1, streaming service content is, for example, videocontent 100, and the video content 100 includes a plurality of segments,e.g., five segments, i.e., a segment #1 110, a segment #2 120, a segment#3 130, a segment #4 140, and a segment #5 150. The segment #1 110includes a plurality of chunks, e.g., two chunks, i.e., a chunk #1 111and a chunk #2 113, the segment #2 120 includes a chunk #1 121, and thesegment #3 130 includes a plurality of chunks, e.g., two chunks, i.e., achunk #1 131 and a chunk #2 133.

An example of a format of streaming service content in a communicationsystem supporting a plurality of radio access interfaces according to anembodiment of the present disclosure has been described with referenceto FIG. 1, and another example of a format of streaming service contentin a communication system supporting a plurality of radio accessinterfaces according to an embodiment of the present disclosure will bedescribed with reference to FIG. 2.

FIG. 2 schematically illustrates another example of a format ofstreaming service content in a communication system supporting aplurality of radio access interfaces according to an embodiment of thepresent disclosure.

Referring to FIG. 2, streaming service content is, for example, videocontent 200, and the video content 200 includes a plurality of segments,e.g., 12 segments, i.e., a segment #1 211, a segment #2 213, a segment#3 215, a segment #4 217, a segment #5 219, a segment #6 221, a segment#7 223, a segment #8 225, a segment #9 227, a segment #10 229, a segment#11 231, and a segment #12 233.

And, the segment #2 213 and the segment #3 215 configure a chuck #2 237,the segment #6 221 and the segment #7 223 configure a chuck #1 239, andthe segment #8 225, the segment #9 227, and the segment #10 229configure a chuck #2 241. Here, each of the segment #2 213, the segment#3 215, the segment #6 221, the segment #7 223, the segment #8 225, thesegment #9 227, and the segment #10 229 has a segment size less than athreshold segment size and may be configured as a chuck as describedabove.

Another example of a format of streaming service content in acommunication system supporting a plurality of radio access interfacesaccording to an embodiment of the present disclosure has been describedwith reference to FIG. 2, and a fast pre-fetching process for astreaming service in a communication system supporting a plurality ofradio access interfaces according to an embodiment of the presentdisclosure will be described with reference to FIG. 3.

FIG. 3 schematically illustrates a fast pre-fetching process for astreaming service in a communication system supporting a plurality ofradio access interfaces according to an embodiment of the presentdisclosure.

Referring to FIG. 3, the communication system includes a station 311 anda sever 313.

The server 313 provides a streaming service, and may be, for example, aserver operating a site such YouTube, Netflix, and the like.

The station 311 may be provided with a streaming service from the server313 and may include a plurality of radio access interfaces. In FIG. 3,it will be assumed that the station 311 includes two radio accessinterfaces, e.g., a Wi-Fi interface and an LTE interface. Further, itwill be assumed that all of the Wi-Fi interface and the LTE interfaceare available.

Firstly, upon detecting that a streaming service provision request suchas a playback start command, a seek command, and the like, the station311 may decrease pre-buffering time for playing a streaming serviceusing the plurality of radio access interfaces. Specially, the station311 predicts a network speed, i.e., an available bandwidth for each ofthe Wi-Fi interface and the LTE interface upon receiving streamingservice data through the Wi-Fi interface and the LTE interface.Hereinafter, for convenience, it will be noted that the network speedand the available bandwidth may be used at the same time or may beinterchangeable each other.

A process of estimating a network speed for each of a plurality of radioaccess interfaces in a station will be described below.

Firstly, the station may estimate a network speed based on amount ofstreaming service data received during each unit time, and this may beexpressed as Equation 1.

$\begin{matrix}{{{network}\mspace{14mu} {speed}} = {{{network}\mspace{14mu} {speed}\; \times \beta} + {\frac{{the}\mspace{14mu} {number}\mspace{14mu} {of}\mspace{14mu} {received}\mspace{14mu} {bits}}{\Delta} \times \left( {1 - \beta} \right)}}} & \left\lbrack {{Equation}\mspace{14mu} 1} \right\rbrack\end{matrix}$

In Equation 1, β is a preset value, and may be varied corresponding to asituation of a mobile communication system.

Secondly, the station may estimate a network speed based on amount ofstreaming service data received every preset time from time at which thestation starts receiving a chunk through each radio access interface,and this may be expressed as Equation 2.

$\begin{matrix}{{{network}\mspace{14mu} {speed}} = \frac{{the}\mspace{14mu} {number}\mspace{14mu} {of}\mspace{14mu} {received}\mspace{14mu} {bits}}{t - t_{0}}} & \left\lbrack {{Equation}\mspace{14mu} 2} \right\rbrack\end{matrix}$

In Equation 2, t₀ denotes time at which chunk reception is startedthrough a corresponding radio access interface, t denotes time at whicha network speed is estimated for a corresponding radio access interface,and t-t0 denotes set time.

Meanwhile, as shown in FIG. 3, it will be assumed that the server 311transmits a segment #1 315, a segment #2 317, and a segment #3 319, andeach of the segment #1 315, the segment #2 317, and the segment #3 319includes two chunks. That is, the segment #1 315 includes a chunk #1315-1 and a chunk #2 315-2, the segment #2 317 includes a chunk #1 317-1and a chunk #2 317-2, and the segment #3 319 includes a chunk #1 319-1and a chunk #2 319-2.

A chunk #1, i.e., the chunk #1 315-1, the chunk #1 317-1, and the chunk#1 319-1 which the segment #1 315, the segment #2 317, and the segment#3 319 include, respectively, are provided to the station 311 throughthe Wi-Fi interface, and a chunk #2, i.e., the chunk #2 315-2, the chunk#2 317-2, and the chunk #2 319-2 which the segment #1 315, the segment#2 317, and the segment #3 319 include, respectively, are provided tothe station 311 through the LTE interface.

That is, the station 311 transmits, to the server 313 through the Wi-Fiinterface, a message, e.g., an HTTP range message to request to providethe chunk #1, i.e., the chunk #1 315-1, the chunk #1 317-1, and thechunk #1 319-1 which the segment #1 315, the segment #2 317, and thesegment #3 319 include, respectively, and transmits, to the server 313through the LTE interface, a message, e.g., an HTTP range message torequest to provide the chunk #2, i.e., the chunk #2 315-2, the chunk #2317-2, and the chunk #2 319-2 which the segment #1 315, the segment #2317, and the segment #3 319 include, respectively. Here, the HTTP rangemessage may is included in an HTTP GET message, and the HTTP message mayinclude Itag indicating a specific streaming file and a range indicatingdata of a specific range, and the Itag and range are a request UniformResource Identifier (URI). That is, an existing request for streamingservice data performed using one HTTP GET message is performed with arequest for streaming service data for each of a plurality of radioaccess interfaces using a plurality of HTTP range messages.

After receiving the HTTP range message from each of the Wi-Fi interfaceand the LTE interface of the station 311, the server 313 transmits anHTTP 200 OK message to each of the Wi-Fi interface and the LTE interfaceand provides data requested from each of the Wi-Fi interface and the LTEinterface along with the HTTP 200 OK message to each of the Wi-Fiinterface and the LTE interface.

Here, an operation between the station 311 and the server 313 will bedescribed below.

Firstly, a case that the station 311 does not recognize an availablebandwidth/network sped of each of the Wi-Fi interface and the LTEinterface will be described below.

The station 311 does not recognize the available bandwidth/network spedof each of the Wi-Fi interface and the LTE interface, so the station 311requests a chunk of the same size from the server 313 at each of theWi-Fi interface and the LTE interface, and receives the chunk of thesame size from the server 313 through each of the Wi-Fi interface andthe LTE interface.

Alternatively, even though the station 311 does not recognize theavailable bandwidth/network sped of each of the Wi-Fi interface and theLTE interface, if there is a preset chunk size for each of the Wi-Fiinterface and the LTE interface, the station 311 requests a chunk of acorresponding size from the server 313 through each of the Wi-Fiinterface and the LTE interface, and receives the chunk of thecorresponding size from the server 313 through each of the Wi-Fiinterface and the LTE interface. Here, a chunk size of each of the Wi-Fiinterface and the LTE interface may be set with various forms, and thechunk size of the Wi-Fi interface may be different from the chunk sizeof the LTE interface.

Secondly, a case that the station 311 recognizes an availablebandwidth/network speed of each of the Wi-Fi interface and the LTEinterface will be described below.

In a case that the station 311 recognizes the availablebandwidth/network speed of each of the Wi-Fi interface and the LTEinterface, the station 311 determines a chunk size of each of the Wi-Fiinterface and the LTE interface based on the available bandwidth/networkspeed of each of the Wi-Fi interface and the LTE interface. Here, thestation 313 may determine the chunk size, for example, proportional to asize of the available bandwidth, and this will be expressed as Equation3 and Equation 4.

$\begin{matrix}{{{LTE}\mspace{14mu} {chunk}\mspace{14mu} {size}} = {{segment}\mspace{14mu} {size} \times \frac{{LTE}\mspace{20mu} {speed}}{{{Wi}\text{-}{Fi}\mspace{11mu} {speed}} + {{LTE}\mspace{11mu} {speed}}}}} & \left\lbrack {{Equation}\mspace{14mu} 3} \right\rbrack\end{matrix}$

In Equation 3, an LTE chunk size denotes a size of a chunk to bereceived through an LTE interface, and an LTE speed denotes a networkspeed in a case that a streaming data service is received through theLTE interface.

$\begin{matrix}{{{Wi}\text{-}{Fi}\mspace{14mu} {chunk}\mspace{14mu} {size}} = {{segment}\mspace{14mu} {size} \times \frac{{Wi}\text{-}{Fi}\mspace{14mu} {speed}}{{{Wi}\text{-}{Fi}\mspace{14mu} {speed}} + {{LTE}\mspace{14mu} {speed}}}}} & \left\lbrack {{Equation}\mspace{14mu} 4} \right\rbrack\end{matrix}$

In Equation 4, a Wi-Fi chunk size denotes a size of a chunk to bereceived through a Wi-Fi interface, and a Wi-Fi speed denotes a networkspeed in a case that a streaming data service is received through theWi-Fi interface.

Various schemes of determining a chunk size of a corresponding radioaccess interface based on the available bandwidth/network speed in thestation 313 may exist, and a detailed description thereof will beomitted herein.

For example, the station 313 determines a chunk size of a correspondingradio access interface based on the available bandwidth/network speed inFIG. 3, however, the station 313 may determine a chunk size of acorresponding radio access interface based on various parameters as wellas the available bandwidth/network speed.

Further, the station 311 requests a chunk of a corresponding size fromthe server 313 through each of the Wi-Fi interface and the LTEinterface, and receives the chunk of the corresponding size from theserver 313 through each of the Wi-Fi interface and the LTE interface.

The station 311 recognizes the available bandwidth/network speed of eachof the Wi-Fi interface and the LTE interface, the station 311 receives achunk from a chunk of which a chunk index is minimum among chunksincluded in a segment through a radio access interface of which anetwork speed is faster. Here, the station 311 may determine a size ofchunk to be received through a corresponding radio access interface witha scheme as described above in Equation 3 and Equation 4, and receiveschunks of which chunk indexes are small through a radio access interfaceof which a network speed is faster.

For example, if a network speed of a Wi-Fi interface is faster, thestation 311 requests a chunk of a determined size from a minimum chunkindex from the server 313 through the Wi-Fi interface, requests a chunkof a determined size which is not requested through the Wi-Fi interfacefrom the server 313, and receives a chunk of a corresponding size fromthe server 313 through each of the Wi-Fi interface and the LTEinterface.

Thirdly, a case that the station 311 recognizes an availablebandwidth/network speed, and stability of each of the Wi-Fi interfaceand the LTE interface will be described below.

The station 311 receives a chunk from a chunk with a minimum chunk indexamong chunks included in a segment through a radio access interface withhigher stability. The station 311 may determine a size of chunk whichwill be received through a corresponding radio access interface using ascheme as described in Equation 3 and Equation 4, and chunks with smallchunk indexes are received through a radio access interface with higherstability. Various schemes of detecting stability in the station 311 mayexist, and a detailed description thereof will be omitted herein.

For example, if stability of an LTE interface is higher, the station 311requests a chunk of a determined size from a minimum chunk index to theserver 313 through the LTE interface, requests a chunk of a determinedsize which is not requested through the LTE interface to the server 313,and receives a chunk of a corresponding size from the server 313 througheach of the Wi-Fi interface and the LTE interface.

Meanwhile, it will be assumed that three operations as described aboveare maintained during preset time, e.g., 10 seconds or until a presetnumber of segments are received.

A fast pre-fetching process for a streaming service in a communicationsystem supporting a plurality of radio access interfaces according to anembodiment of the present disclosure has been described with referenceto FIG. 3, and an example of a load balancing process for a streamingservice in a communication system supporting a plurality of radio accessinterfaces according to an embodiment of the present disclosure will bedescribed with reference to FIG. 4.

FIG. 4 schematically illustrates an example of a load balancing processfor a streaming service in a communication system supporting a pluralityof radio access interfaces according to an embodiment of the presentdisclosure.

Referring to FIG. 4, the communication system includes a station 411 anda sever 413. The server 413 provides a streaming service, and may be,for example, a server operating a site such YouTube, Netflix, and thelike. The station 411 may be provided with a streaming service from theserver 413 and may include a plurality of radio access interfaces. InFIG. 4, it will be assumed that the station 411 includes two radioaccess interfaces, e.g., a Wi-Fi interface and an LTE interface.Further, it will be assumed that all of the Wi-Fi interface and the LTEinterface are available.

The station 411 sets one of the Wi-Fi interface and the LTE interface asa primary radio access interface, and sets the other of the Wi-Fiinterface and the LTE interface as a secondary radio access interface.Here, the station 411 may determine the primary radio access interfacebased on various parameters, e.g., parameters such as billing/charging,power consumption, signal stability, and the like. In FIG. 4, it will beassumed that the Wi-Fi interface is determined as the primary radioaccess interface.

The station 411 receives streaming service data through the primaryradio access interface as possible for maintaining a network speed forthe streaming service data corresponding to an encoding bit rate appliedto a streaming service in the server 413, and receives the streamingservice data through the secondary radio access interface only if thestation 411 is not capable of receiving the streaming service datathrough the primary radio access interface.

As shown in FIG. 4, it will be assumed that the server 413 transmits asegment #4 415, a segment #5 417, and a segment #6 419. The segment #4415, the segment #5 417, and the segment #6 419 are provided to thestation 411 through the Wi-Fi interface. That is, the station 411transmits, to the server 413, a message, e.g., an HTTP range message torequest to provide the segment #4 415, the segment #5 417, and thesegment #6 419.

When the HTTP range message is received through the Wi-Fi interface ofthe station 411, the server 413 transmits an HTTP 200 OK message to theWi-Fi interface of the station 411, and provides data requested from theWi-Fi interface along with the HTTP 200 OK message.

That is, as shown in FIG. 4, a bandwidth consumed in the station 411 is12 Mpbs, the available bandwidth of the Wi-Fi interface is 15 Mpbs, andan encoding bit rate applied to a streaming service in the server 413 is12 Mbps, so the station 411 requests a chunk to the server 413 through aWi-Fi interface as a primary radio access interface, and receives thechunk from the server 413. That is, a load balancing process in a casethat an available bandwidth of a primary radio access interface maysupport a network speed which corresponds to an encoding bit rateapplied to streaming service data which a station intends to receive isshown in FIG. 4.

That is, the station 411 may perform a load balancing operation based ona criterion as expressed in Equation 5. That is, the criterion asexpressed in Equation 5 is satisfied, the station 411 requests a chunkto the server 413 through only a Wi-Fi interface, and receives the chunkfrom the server 413.

$\begin{matrix}{\frac{{Wi}\text{-}{Fi}\mspace{14mu} {{speed}\lbrack{bps}\rbrack}}{{encoding}\mspace{14mu} {bit}\mspace{14mu} {rate}\mspace{14mu} {applied}\mspace{14mu} {to}\mspace{14mu} {streaming}\mspace{14mu} {{service}\mspace{11mu}\lbrack{bps}\rbrack}} \geq 1} & \left\lbrack {{Equation}\mspace{14mu} 5} \right\rbrack\end{matrix}$

Equation 5 means that a Wi-Fi speed is greater than or equal to anencoding bit rate applied to a streaming service, so Equation 5indicates that a Wi-Fi interface may support a network speed whichcorresponds to the encoding bit rate applied to the streaming service.

An example of a load balancing process for a streaming service in acommunication system supporting a plurality of radio access interfacesaccording to an embodiment of the present disclosure has been describedwith reference to FIG. 4, and another example of a load balancingprocess for a streaming service in a communication system supporting aplurality of radio access interfaces according to an embodiment of thepresent disclosure will be described with reference to FIG. 5.

FIG. 5 schematically illustrates another example of a load balancingprocess for a streaming service in a communication system supporting aplurality of radio access interfaces according to an embodiment of thepresent disclosure.

Referring to FIG. 5, the communication system includes a station 511 anda sever 513. The server 513 provides a streaming service, and may be,for example, a server operating a site such YouTube, Netflix, and thelike. The station 511 may be provided with a streaming service from theserver 513 and may include a plurality of radio access interfaces. InFIG. 5, it will be assumed that the station 511 includes two radioaccess interfaces, e.g., a Wi-Fi interface and an LTE interface.Further, it will be assumed that all of the Wi-Fi interface and the LTEinterface are available.

The station 511 sets one of the Wi-Fi interface and the LTE interface asa primary radio access interface, and sets the other of the Wi-Fiinterface and the LTE interface as a secondary radio access interface.Here, the station 511 may determine the primary radio access interfacebased on various parameters, e.g., parameters such as billing/charging,power consumption, signal stability, and the like. In FIG. 5, it will beassumed that the Wi-Fi interface is determined as the primary radioaccess interface.

The station 511 receives streaming service data through the primaryradio access interface as possible for maintaining a network speed forthe streaming service data corresponding to an encoding bit rate appliedto a streaming service in the server 513, and receives the streamingservice data through the secondary radio access interface only if thestation 511 is not capable of receiving the streaming service datathrough the primary radio access interface.

As shown in FIG. 5, it will be assumed that the server 513 transmits asegment #4 515, a segment #5 517, and a segment #6 519. Each of thesegment #4 515, the segment #5 517, and the segment #6 519 includes achunk #1 and a chunk #2. That is, the segment #4 515 includes a chunk #1515-1 and a chunk #2 515-2, the segment #5 517 includes a chunk #1 517-1and a chunk #2 517-2, and the segment #6 519 includes a chunk #1 519-1and a chunk #2 519-2. The chunk #1 515-1, chunk #1 517-1, and chunk #1519-1 are provided to the station 511 through the Wi-Fi interface, andthe chunk #2 515-2, chunk #2 517-2, and chunk #2 519-2 are provided tothe station 511 through the LTE interface.

That is, the station 511 transmits, to the server 513, a message, e.g.,an HTTP range message to request to provide the chunk #1 515-1, chunk #1517-1, and chunk #1 519-1 through the Wi-Fi interface, and transmits, tothe server 513, a message, e.g., an HTTP range message to request toprovide the chunk #2 515-2, chunk #2 517-2, and chunk #2 519-2 throughthe LTE interface.

When the HTTP range message is received from each of the Wi-Fi interfaceand the LTE interface of the station 511, the server 513 transmits anHTTP 200 OK message to each of the Wi-Fi interface and the LTEinterface, and provides data requested from each of the Wi-Fi interfaceand the LTE interface along with the HTTP 200 OK message to each of theWi-Fi interface and the LTE interface.

That is, as shown in FIG. 5, a bandwidth consumed in the station 511 is10 Mpbs, the available bandwidth of the Wi-Fi interface is 10 Mpbs, andan encoding bit rate applied to a streaming service in the server 513 is12 Mbps, so the station 511 may not maintain a network speedcorresponding to the encoding bit rate applied to the streaming servicein the server 513 if the station 511 requests a chunk to the server 513through only the Wi-Fi interface as a primary radio access interface.

So, the station 511 requests a chunk to the server 513 through the LTEinterface as well as the Wi-Fi interface, and receives the chunk fromthe server 513. That is, a load balancing process in a case that anavailable bandwidth of a primary radio access interface may not supporta network speed which corresponds to an encoding bit rate applied tostreaming service data which a station intends to receive is shown inFIG. 5.

That is, the station 511 may perform a load balancing operation based onthe criterion as expressed in Equation 5. That is, if the criterion asexpressed in Equation 5 is not satisfied, the station 511 requests achunk to the server 513 through an LTE interface as well as a Wi-Fiinterface, and receives the chunk from the server 513. That is, a casethat the criterion as expressed in Equation 5 is not satisfied meansthat a Wi-Fi speed is less than an encoding bit rate applied to astreaming service, so the case indicates that the Wi-Fi interface is notcapable of supporting a network speed which corresponds to the encodingbit rate applied to the streaming service.

In this case, the station 511 may determine a chunk size of a chunkwhich the station 511 will receive through the Wi-Fi interface and achunk size of a chunk which the station 511 will receive through the LTEinterface based on Equation 6 and Equation 7.

$\begin{matrix}{{{Wi}\text{-}{Fi}\mspace{14mu} {chunk}\mspace{14mu} {size}} = {{segment}\mspace{14mu} {size} \times \frac{{Wi}\text{-}{Fi}\mspace{14mu} {{speed}\lbrack{bps}\rbrack}}{{encoding}\mspace{14mu} {bit}\mspace{14mu} {rate}\mspace{14mu} {applied}\mspace{14mu} {to}\mspace{14mu} {streaming}\mspace{14mu} {{service}\lbrack{bps}\rbrack}}}} & \left\lbrack {{Equation}\mspace{14mu} 6} \right\rbrack \\{{{LTE}\mspace{14mu} {chunk}\mspace{14mu} {size}} = {{segment}\mspace{14mu} {size} \times \left( {1 - \frac{{Wi}\text{-}{Fi}\mspace{14mu} {{speed}\lbrack{bps}\rbrack}}{1\mspace{14mu} {encoding}\mspace{14mu} {bit}\mspace{20mu} {rate}\mspace{14mu} {applied}\mspace{14mu} {to}\mspace{14mu} {streaming}\mspace{14mu} {{service}\lbrack{bps}\rbrack}}} \right)}} & \left\lbrack {{Equation}\mspace{14mu} 7} \right\rbrack\end{matrix}$

Meanwhile, a situation of a mobile communication is always changeable,so the station 511 may set a target network speed which the station 511targets to a value which is larger than the encoding bit rate applied tothe streaming service by a preset value, e.g., a. In this case, Equation6 and Equation 7 may be changed to Equation 8 and Equation 9. The a maybe greater than or equal to 0 (α≧0).

$\begin{matrix}{{{Wi}\text{-}{Fi}\mspace{14mu} {chunk}\mspace{14mu} {size}} = {{segment}\mspace{14mu} {size} \times \frac{{Wi}\text{-}{Fi}\mspace{14mu} {{speed}\lbrack{bps}\rbrack}}{{{encoding}\mspace{14mu} {bit}\mspace{14mu} {rate}\mspace{14mu} {applied}\mspace{14mu} {to}\mspace{14mu} {streaming}\mspace{14mu} {service}} + {\alpha \;\lbrack{bps}\rbrack}}}} & \left\lbrack {{Equation}\mspace{14mu} 8} \right\rbrack \\{{{LTE}\mspace{14mu} {chunk}\mspace{14mu} {size}} = {{segment}\mspace{14mu} {size} \times \left( {1 - \frac{{Wi}\text{-}{Fi}\mspace{14mu} {{speed}\lbrack{bps}\rbrack}}{{{encoding}\mspace{14mu} {bit}\mspace{14mu} {rate}\mspace{14mu} {applied}\mspace{14mu} {to}\mspace{14mu} {streaming}\mspace{14mu} {service}} + {\alpha \;\lbrack{bps}\rbrack}}} \right)}} & \left\lbrack {{Equation}\mspace{14mu} 9} \right\rbrack\end{matrix}$

An operation of determining a chunk size of a chunk to be receivedthrough a Wi-Fi interface and a chunk size of a chunk to be receivedthrough an LTE interface based on Equations 6 to 9 in a case that thecriterion as expressed in Equation 5 is not satisfied has been describedabove.

Alternatively, the station 511 may perform a load balancing operationbased on download time consumed for receiving a corresponding segment,this will be described below.

Firstly, upon downloading each segment at a network speed whichcorrespond to an encoding bit rate applied to a streaming service, thestation 511 calculates download time consumed for completing downloadfor each segment.

The station 511 detects amount of data which is possible to be receivedthrough a primary radio access interface during the download time basedon an available bandwidth/network speed of the primary radio accessinterface. The station 511 receives a segment through the primary radioaccess interface if the detected amount of the data which is possible tobe received through the primary radio access interface during thedownload time is greater than or equal to a segment size.

If the detected amount of the data which is possible to be receivedthrough the primary radio access interface during the download time isless than the segment size, the station 511 requests and receives,through the primary radio access interface, a part, e.g., a chunk #1 ofa segment which corresponds to the determined amount of the data whichis possible to be received through the primary radio access interfaceduring the download time, and requests and receives a remaining part,e.g., a chunk #2 of the segment through a secondary radio accessinterface. That is, if the station 511 downloads at the network speedwhich corresponds to the encoding bit rate applied to the streamingservice, the station 511 may determine whether to receive streamingservice data using the primary radio access interface or using both theprimary radio access interface and the secondary radio access interfacebased on the download time.

A case that the station 511 determines whether to receive the streamingservice data using only the primary radio access interface or using boththe primary radio access interface and the secondary radio accessinterface based on the encoding bit rate applied to the streamingservice and the download time has been described above, however, asituation of a mobile communication system is always changeable, so thestation 511 may set the target network speed which the station 511targets to a value which is greater than the encoding bit rate appliedto the streaming service by the preset value a.

Another example of a load balancing process for a streaming service in acommunication system supporting a plurality of radio access interfacesaccording to an embodiment of the present disclosure has been describedwith reference to FIG. 5, and an example of detailed implementation of aload balancing process for a streaming service in a communication systemsupporting a plurality of radio access interfaces according to anembodiment of the present disclosure will be described with reference toFIG. 6.

FIG. 6 schematically illustrates an example of detailed implementationof a load balancing process for a streaming service in a communicationsystem supporting a plurality of radio access interfaces according to anembodiment of the present disclosure.

Referring to FIG. 6, it will be assumed that a station (not shown inFIG. 6) sets a primary radio access interface to a Wi-Fi interface (611)and sets a secondary radio access interface to an LTE interface (613).Here, it will be assumed that a network speed of the Wi-Fi interface is5 Mbps, and a network speed of the LTE interface is 10 Mbps.

Further, it will be assumed that a server (not shown in FIG. 6) appliesan encoding bit rate of 8 Mbps to a streaming service, e.g., a videoservice (615).

It will be assumed that a size of video contents which the station wantsto receive is 10 gigabits (GBs) (617). It will be assumed that the videocontents include a plurality of segments, and a size of each of theplurality of segments is 30 megabits (MBs) (619). So, in a case that itwill be assumed that 8 Mbps as the encoding bit rate applied to thevideo contents is a network speed, download time consumed fordownloading one segment with a size of 30 MB is 30 seconds (621).

Meanwhile, a network speed of the Wi-Fi interface as the primary radioaccess interface is 5 Mbps, so the Wi-Fi interface is not capable ofsupporting 8 Mbps as the encoding bit rate applied to the videocontents. However, the Wi-Fi interface is the primary radio accessinterface, so the station determines a chunk size such that the stationmay use the Wi-Fi interface as maximum as possible. That is, the stationdetermines amount of data which the station may receive during 30seconds as the download time at 5 Mbps as a network speed of the Wi-Fiinterface as 18.75 MBs, so the station determines a size of a chunk,i.e., a Wi-Fi chunk which may be received through the Wi-Fi interfaceamong chunks included in each segment as 18.75 MBs (623).

Further, a chunk of a size of 18.75 MBs among each segment may bereceived through the Wi-Fi interface, so the station receives aremaining chunk except for a Wi-Fi chunk among chunks included in eachchunk through an LTE interface. A chunk received through the LTEinterface will be referred to as LTE chunk, so a size of the LTE chunkis 11.25 MBs (=30 MBs-18.75 MBs), and the LTE chunk is received during 9seconds (625).

Meanwhile, FIG. 6 focuses on a description of an operation of receivinga Wi-Fi chunk and an LTE chunk in a station, however, it will be notedthat the station as described above performed an operation of requestinga corresponding chunk from a server already in order for receiving theWi-Fi chunk and the LTE chunk as described in FIG. 6.

An example of detailed implementation of a load balancing process for astreaming service in a communication system supporting a plurality ofradio access interfaces according to an embodiment of the presentdisclosure has been described with reference to FIG. 6, and relationbetween a network speed and download time according to detailedimplementation of a load balancing process for a streaming service in acommunication system supporting a plurality of radio access interfacesas shown in FIG. 6 will be described with reference to FIG. 7.

FIG. 7 schematically illustrates relation between a network speed anddownload time according to detailed implementation of a load balancingprocess for a streaming service in a communication system supporting aplurality of radio access interfaces as shown in FIG. 6.

Referring to FIG. 7, relation between a network speed and download timeas shown in FIG. 7 indicates relation between a network speed anddownload time in a case that an LTE chunk and a Wi-Fi chunk aredetermined as described in FIG. 6. That is, relation between a networkspeed and download time as shown in FIG. 7 indicates relation between anetwork speed and download time in a case that a station receives an LTEchunk 711 of a size of 11.25 MBs during 9 seconds through an LTEinterface, and receives a Wi-Fi chunk 713 of a size of 18.75 MBs during30 seconds through a Wi-Fi interface as described in FIG. 6.

Relation between a network speed and download time according to detailedimplementation of a load balancing process for a streaming service in acommunication system supporting a plurality of radio access interfacesas shown in FIG. 6 has been described with reference to FIG. 7, and anexample of a stability guaranteeing process for a streaming service in acommunication system supporting a plurality of radio access interfacesaccording to an embodiment of the present disclosure will be describedwith reference to FIG. 8.

FIG. 8 schematically illustrates an example of a stability guaranteeingprocess for a streaming service in a communication system supporting aplurality of radio access interfaces according to an embodiment of thepresent disclosure.

Referring to FIG. 8, as described above, in a case of a streamingservice, it may be operated as an important factor affecting a servicequality to maintain a network speed corresponding to an encoding bitrate applied to a streaming service in a server. So, a station needs tocontinuously monitor whether streaming service data is normally receivedthrough each radio access interface.

Firstly, the station monitors a network speed of each of radio accessinterfaces at step 811 and proceeds to step 813. That is, the stationmonitors the network speed of each of the radio access interfaces forchecking whether corresponding chunks are received at a network speeddetermined at time that a chunk is requested when receiving a segment atstep 813. Here, it will be assumed that the monitor interval ismaintained during preset time, e.g., 10 seconds or until a preset numberof segments are received.

At step 813, the station determines whether there is a radio accessinterface receiving streaming service data at a network speed less thana threshold network speed. Here, the threshold network speed may be setto the encoding bit rate applied to the streaming service, or a valuewhich is less than the encoding bit rate by a preset value, e.g., (β.Here, β may be greater than or equal to 0 (β≧0).

If there is the radio access interface receiving the streaming servicedata at the network speed less than the threshold network speed, thestation proceeds to step 815. At step 815, upon receiving streamingservice data through the radio access interface receiving the streamingservice data at the network speed less than the threshold network speed,the station may not maintain the network speed which corresponds to theencoding bit rate applied to the streaming service, so the stationperforms an adjusting operation that controls a part of amount ofstreaming service data which are received through the radio accessinterface receiving the streaming service data at the network speed lessthan the threshold network speed to be received through another radioaccess interface receiving the streaming service data at a network speedwhich is greater than or equal to the threshold network speed. Here, ina case that the network speed corresponding to the encoding bit rateapplied to the streaming service when the streaming service data isreceived through only the another radio access interface, the stationmay receive the streaming service data through only the another radioaccess interface.

Meanwhile, FIG. 8 focuses on a description of an operation of receivinga Wi-Fi chunk and an LTE chunk in a station, however, it will be notedthat the station as described above performed an operation of requestinga corresponding chunk from a server already in order for receiving theWi-Fi chunk and the LTE chunk as described in FIG. 8.

Although FIG. 8 illustrates an example of a stability guaranteeingprocess for a streaming service in a communication system supporting aplurality of radio access interfaces according to an embodiment of thepresent disclosure, various changes could be made to FIG. 8. Forexample, although shown as a series of operations, various operations inFIG. 8 could overlap, occur in parallel, occur in a different order, oroccur multiple times.

An example of a stability guaranteeing process for a streaming servicein a communication system supporting a plurality of radio accessinterfaces according to an embodiment of the present disclosure has beendescribed with reference to FIG. 8, and another example of a stabilityguaranteeing process for a streaming service in a communication systemsupporting a plurality of radio access interfaces according to anembodiment of the present disclosure will be described with reference toFIG. 9.

FIG. 9 schematically illustrates another example of a stabilityguaranteeing process for a streaming service in a communication systemsupporting a plurality of radio access interfaces according to anembodiment of the present disclosure.

Referring to FIG. 9, as described above, in a case of a streamingservice, it may be operated as an important factor affecting a servicequality to maintain a network speed corresponding to an encoding bitrate applied to a streaming service in a server. So, received signalstrength also affects a service quality, so a station needs tocontinuously monitor whether streaming service data is normally receivedthrough each radio access interface. Here, the received signal strengthmay be determined based on, for example, various metrics such asreceived signal code power (RSCP), reference signal received power(RSRP), a reference signal strength indicator (RSSI), a reference signalreceived quality (RSRQ), a carrier-to-interference noise ratio (CINR), asignal-to-noise ratio (SNR), a block error rate (BLER), and the like.

Firstly, the station monitors a network speed of each of radio accessinterfaces at step 911 and proceeds to step 913. That is, the stationmonitors the network speed of each of the radio access interfaces forchecking whether corresponding chunks are received at a network speeddetermined at time that a chunk is requested upon receiving a segment atstep 913. Here, it will be assumed that the monitor interval ismaintained during preset time, e.g., 10 seconds or until a preset numberof segments are received.

The station determines whether there is a radio access interfacereceiving streaming service data with received signal strength less thanthreshold received signal strength at step 913. Here, the thresholdreceived signal strength may be appropriately set according to asituation of a mobile communication system, and an operation of settingthe threshold received signal strength will be omitted herein.

If there is the radio access interface receiving the streaming servicedata with the received signal strength less than the threshold receivedsignal strength, the station proceeds to step 915. At step 915, if thestation receives the streaming service data through a radio accessinterface receiving the streaming service data with the received signalstrength less than the threshold received signal strength, the stationmay not maintain the network speed which corresponds to the encoding bitrate applied to the streaming service, so the station performs anadjusting operation in which the station receives a part of streamingservice data amount received through the radio access interfacereceiving the streaming service data with the received signal strengthless than the threshold received signal strength through a radio accessinterface receiving the streaming service data with received signalstrength greater than or equal to the threshold received signalstrength. Here, in a case that the network speed which corresponds tothe encoding bit rate applied to the streaming service may be maintainedif the streaming service data is received through only the other radioaccess interface, the station may receive the streaming service datathrough only the other radio access interface.

Meanwhile, FIG. 9 focuses on a description of an operation of receivinga Wi-Fi chunk and an LTE chunk in a station, however, it will be notedthat the station as described above performed an operation of requestinga corresponding chunk from a server already in order for receiving theWi-Fi chunk and the LTE chunk as described in FIG. 9.

Although FIG. 9 illustrates another example of a stability guaranteeingprocess for a streaming service in a communication system supporting aplurality of radio access interfaces according to an embodiment of thepresent disclosure, various changes could be made to FIG. 9. Forexample, although shown as a series of operations, various operations inFIG. 9 could overlap, occur in parallel, occur in a different order, oroccur multiple times.

Another example of a stability guaranteeing process for a streamingservice in a communication system supporting a plurality of radio accessinterfaces according to an embodiment of the present disclosure has beendescribed with reference to FIG. 9, and still another example of astability guaranteeing process for a streaming service in acommunication system supporting a plurality of radio access interfacesaccording to an embodiment of the present disclosure will be describedwith reference to FIG. 10.

FIG. 10 schematically illustrates still another example of a stabilityguaranteeing process for a streaming service in a communication systemsupporting a plurality of radio access interfaces according to anembodiment of the present disclosure.

Referring to FIG. 10, as described above, in a case of a streamingservice, it may be operated as an important factor affecting a servicequality to maintain a network speed corresponding to an encoding bitrate applied to a streaming service in a server. So, a station needs tocontinuously monitor whether streaming service data is normally receivedthrough each radio access interface. In FIG. 10, a station monitors anetwork speed and available bandwidth of a corresponding radio accessinterface while receiving a chunk through each of radio accessinterfaces in order to maintain a network speed corresponding to anencoding bit rate applied to a streaming service.

Firstly, the station monitors a network speed of each of radio accessnetworks while a part of a segment, i.e., a chunk through each of theradio access networks at step 1011 and proceeds to step 1013. That is,the station monitors the network speed of each of the radio accessnetworks for checking whether corresponding chunks are received at anetwork speed as determined when the corresponding chunks are requestedupon receiving a segment, and proceeds to step 1013. Here, it will beassumed that the monitor interval is maintained during preset time,e.g., 10 seconds or until a preset number of segments are received.

At step 1013, the station determines whether there is a radio accessinterface receiving streaming service data at a network speed less thanthe first threshold network speed. Here, the first threshold networkspeed may be set to the encoding bit rate applied to the streamingservice, or a value which is less than the encoding bit rate by a presetvalue, e.g., β. Here, β may be greater than or equal to 0 (62 ≧0). Here,the first threshold network speed may be set to an arbitrary value.

If there is the radio access interface receiving the streaming servicedata at the network speed less than the first threshold network speed,the station proceeds to step 1015. Here, the station requests to theserver such that the station may receive a remaining part, i.e., a partto be received among a chunk which is receiving through a radio accessinterface receiving the streaming service data through a radio accessinterface other than the radio access interface receiving the streamingservice data at the network speed less than the first threshold networkspeed. Here, the request may be performed using an HTTP range requestmessage.

If the other radio access interface receives the streaming service dataalready, the other radio access interface may additionally establish anHTTP session with the server, and receive the remaining part of thestreaming service data, i.e., the chunk from the server through theadditionally established HTTP session at step 1021. Here, an availablebandwidth of the other radio access interface at least needs to beguaranteed such that the other radio access interface may receive theremaining part of the chunk. If the available bandwidth of the otherradio access interface is not guaranteed such that the other radioaccess interface may receive the remaining part of the chunk, theadditional HTTP session is not established.

The station determines whether there is a radio access interfacereceiving the streaming service data at a network speed less than thesecond threshold network speed among radio access interfaces receivingthe streaming service data at the first threshold network speed at step1015. Here, the second threshold network speed may be set to a valueless than the first threshold network speed. If there is no radio accessinterface receiving the streaming service data at the network speed lessthan the second threshold network speed, the station proceeds to step1017.

The station determines whether the radio access interface receiving thestreaming service data at the network speed less than the firstthreshold network speed receives the streaming service data at thenetwork speed less than the first threshold network speed during presettime at step 1017. If the radio access interface receiving the streamingservice data at the network speed less than the first threshold networkspeed does not receive the streaming service data at the network speedless than the first threshold network speed during the preset time, thestation returns to step 1011.

If the radio access interface receiving the streaming service data atthe network speed less than the first threshold network speed receivesthe streaming service data at the network speed less than the firstthreshold network speed during the preset time, the station proceeds tostep 1019. The station determines not to receive the streaming servicethrough a corresponding radio access interface at step 1019. That is,the station terminates an HTTP session established between thecorresponding radio access interface and the server at step 1019. So,thereafter, the station receives the streaming service data through onlyradio access interfaces other than the radio access interface of whichthe HTTP session is terminated.

If there is the radio access interface receiving the streaming servicedata at the network speed less than the second threshold network speedat step 1015, the station proceeds to step 1019. The station determinesnot to receive the streaming service through a corresponding radioaccess interface at step 1019. That is, the station terminates an HTTPsession established between the corresponding radio access interface andthe server at step 1019. So, thereafter, the station receives thestreaming service data through only radio access interfaces other thanthe radio access interface of which the HTTP session is terminated.

For example, a case that a corresponding HTTP session is terminated ifit is determined not to receive a streaming service through acorresponding radio access interface has been described in FIG. 10.Further, a corresponding HTTP session is terminated and a chunk whichcorresponds to threshold streaming service data amount may becontinuously requested and received for future use for the correspondinginterface in a case that it is determined not to receive the streamingservice through the corresponding radio access interface. Here, thethreshold streaming service data amount may be set to amount suitablefor checking a keep-alive state for a corresponding HTTP session.

In a process as described in FIG. 10, in a case that use of the radioaccess interface of which the HTTP session is terminated is possibleafter reception of a corresponding segment has been completed, thestation may receive streaming service data through the radio accessinterface of which the HTTP session is terminated again. In this case,the time during which the streaming service data is received at thenetwork speed less than the first threshold network speed detected atstep 1018 is reset.

Meanwhile, FIG. 10 focuses on a description of an operation of receivinga chunk in a station, however, it will be noted that the station asdescribed above performed an operation of requesting a correspondingchunk from a server already in order for receiving the chunk asdescribed in FIG. 10.

Although FIG. 10 illustrates still another example of a stabilityguaranteeing process for a streaming service in a communication systemsupporting a plurality of radio access interfaces according to anembodiment of the present disclosure, various changes could be made toFIG. 10. For example, although shown as a series of operations, variousoperations in FIG. 10 could overlap, occur in parallel, occur in adifferent order, or occur multiple times.

Still another example of a stability guaranteeing process for astreaming service in a communication system supporting a plurality ofradio access interfaces according to an embodiment of the presentdisclosure has been described with reference to FIG. 10, and relationamong a network speed and radio access interfaces according to stillanother example of a reliability guaranteeing process for a streamingservice in a communication system supporting a plurality of radio accessinterfaces as shown in FIG. 10 will be described with reference to FIG.11. FIG. 11 schematically illustrates relation among a network speed andradio access interfaces according to still another example of astability guaranteeing process for a streaming service in acommunication system supporting a plurality of radio access interfacesas shown in FIG. 10.

Referring to FIG. 11, relation between a network speed and radio accessinterfaces as shown in FIG. 11 indicates relation between a networkspeed and radio access interfaces in a case that radio access interfacesare used as described in FIG. 10. That is, relation between a networkspeed and radio access interfaces as shown in FIG. 11 indicates relationbetween a network speed and radio access interfaces, i.e., a Wi-Fiinterface and an LTE interface may be determined based on the firstthreshold network speed and the second threshold network speed asdescribed in FIG. 10.

Relation among a network speed and radio access interfaces according tostill another example of a stability guaranteeing process for astreaming service in a communication system supporting a plurality ofradio access interfaces as shown in FIG. 10 has been described withreference to FIG. 11, and a process of differently setting a networkspeed per radio access interface as still another example of a stabilityguaranteeing process for a streaming service in a communication systemsupporting a plurality of radio access interfaces will be describedbelow.

Firstly, a threshold network speed for a radio access interfacereceiving a chunk may be set to an encoding bit rate applied to videocontent. The reason why the threshold network speed for the radio accessinterface receiving the chunk may be set to the encoding bit rateapplied to the video content will be described below.

Firstly, the first chunk is transferred to a video player application,and the video player application does not perform a playback operationif the video player application is not capable of reading video contentswhich correspond to an encoding bit rate applied to the video content.For example, in a case that the first chunk is received through an LTEinterface, if a network speed of the LTE interface is greater than orequal to the encoding bit rate applied to the video content, there is noneed for an operation for guaranteeing stability. Secondly, a thresholdnetwork speed for a radio access interface receiving a chunk may bedetermined after the first chunk is received. The second chunk isbuffered while the first chunk is read, the second chunk is bufferedwhile the first chunk is read at a video player application. So, aproblem does not occur while the second chunk is buffered even though anetwork speed of a radio access interface receiving the second chunk isrelatively slow. So, if download for the second chunk has not beencompleted and a speed of the radio access interface receiving the secondchunk does not satisfies a criterion as expressed in Equation 10 afterdownload for the first chunk has been completed, a stabilityguaranteeing operation is performed. That is, a threshold network speedof a radio access interface receiving the second chunk may be set asexpressed in Equation 10.

$\begin{matrix}{{{{TH}\mspace{11mu} \sec} = \frac{S}{T}}{\mspace{14mu} \mspace{14mu}}} & \left\lbrack {{Equation}\mspace{14mu} 10} \right\rbrack\end{matrix}$

In Equation (10), THsec denotes a threshold network speed for the radioaccess interface receiving the second chunk, S denotes amount ofremaining streaming service data which is not received among the secondchunk, and T denotes time until which reception for streaming servicedata which corresponds to the S needs to be completed, i.e., time untilwhich download for the streaming service data which corresponds to the Sneeds to be completed.

Further, the T may be expressed as Equation 11.

$\begin{matrix}{{T = \mspace{14mu} {\frac{\begin{matrix}{{total}\mspace{14mu} {size}\mspace{14mu} {of}\mspace{14mu} {the}} \\{{second}\mspace{14mu} {chunk}}\end{matrix}}{{videobitrate}\mspace{20mu}} - \begin{matrix}{{time}\mspace{14mu} {consumed}\mspace{14mu} {for}\mspace{14mu} {received}} \\{{streaming}\mspace{14mu} {service}\mspace{14mu} {among}} \\{{the}\mspace{14mu} {second}\mspace{14mu} {chunk}}\end{matrix}}}\mspace{14mu}} & \left\lbrack {{Equation}\mspace{14mu} 11} \right\rbrack\end{matrix}$

A process of differently setting a network speed per radio accessinterface as still another example of a stability guaranteeing processfor a streaming service in a communication system supporting a pluralityof radio access interfaces has been described above, and still anotherexample of a stability guaranteeing process for a streaming service in acommunication system supporting a plurality of radio access interfacesaccording to an embodiment of the present disclosure will be describedwith reference to FIG. 12.

FIG. 12 schematically illustrates still another example of a stabilityguaranteeing process for a streaming service in a communication systemsupporting a plurality of radio access interfaces according to anembodiment of the present disclosure.

Referring to FIG. 12, as described above, in a case of a streamingservice, it may be operated as an important factor affecting a servicequality to maintain a network speed corresponding to an encoding bitrate applied to a streaming service in a server. So, a station needs tocontinuously monitor whether streaming service data is normally receivedthrough each radio access interface. In FIG. 12, a station monitors anetwork speed and available bandwidth of a corresponding radio accessinterface while receiving a chunk through each of radio accessinterfaces in order to maintain a network speed corresponding to theencoding bit rate applied to the streaming service.

Firstly, the station monitors a network speed and an available bandwidthof each of radio access networks while receiving a part of a segment,i.e., a chunk through each of the radio access networks at step 1211 andproceeds to step 1213. That is, the station monitors the network speedand the available bandwidth of each of the radio access networks forchecking whether corresponding chunks are received at a network speed asdetermined when the corresponding chunks are requested upon receiving asegment, and proceeds to step 1213. Here, it will be assumed that themonitor interval is maintained during preset time, e.g., 10 seconds oruntil a preset number of segments are received.

At step 1213, the station determines whether there is a radio accessinterface receiving streaming service data at a network speed less thanthe first threshold network speed. Here, the first threshold networkspeed may be set to the encoding bit rate applied to the streamingservice, or a value which is less than the encoding bit rate by a presetvalue, e.g., β. Here, β may be greater than or equal to 0 (β≧0). Here,the first threshold network speed may be set to an arbitrary value.

If there is the radio access interface receiving the streaming servicedata at the network speed less than the first threshold network speed,the station proceeds to step 1215. Here, the station requests to theserver such that the station may receive a chunk which is receivingthrough the radio access interface receiving the streaming service dataat the network speed less than the first threshold network speed througha radio access interface other than the radio access interface receivingthe streaming service data at the network speed less than the firstthreshold network speed. Here, the request may be performed using anHTTP range request message.

If the other radio access interface receives the streaming service dataalready, the other radio access interface may additionally establish anHTTP session with the server, and receive the streaming service data,i.e., the chunk from the server through the additionally establishedHTTP session at step 1221. Here, an available bandwidth of the otherradio access interface at least needs to be guaranteed such that theother radio access interface may receive the chunk. If the availablebandwidth of the other radio access interface is not guaranteed suchthat the other radio access interface may receive the remaining part ofthe chunk, the additional HTTP session is not established. As a result,in FIG. 12, a station receives the same chunk through a plurality ofradio access interfaces in order to guarantee stability for reception ofthe streaming service. That is, the station guarantees the stability forthe reception of the streaming service by receiving a correspondingchunk through the other radio access interface even though the radioaccess interface receiving the streaming service data at the firstthreshold network speed receives the corresponding chunk.

The station determines whether there is a radio access interfacereceiving the streaming service data at the second threshold networkspeed among radio access interfaces receiving the streaming service dataat the first threshold network speed at step 1215. Here, the secondthreshold network speed may be set to a value less than the firstthreshold network speed. If there is no radio access interface receivingthe streaming service data at the network speed less than the secondthreshold network speed, the station proceeds to step 1217.

The station determines whether the radio access interface receiving thestreaming service data at the network speed less than the firstthreshold network speed receives the streaming service data at thenetwork speed less than the first threshold network speed during presettime at step 1217. If the radio access interface receiving the streamingservice data at the network speed less than the first threshold networkspeed does not receive the streaming service data at the network speedless than the first threshold network speed during the preset time, thestation returns to step 1211.

If the radio access interface receiving the streaming service data atthe network speed less than the first threshold network speed receivesthe streaming service data at the network speed less than the firstthreshold network speed during the preset time, the station proceeds tostep 1219. The station determines not to receive the streaming servicethrough a corresponding radio access interface at step 1219. That is,the station terminates an HTTP session established between thecorresponding radio access interface and the server at step 1219. So,thereafter, the station receives the streaming service data through onlyradio access interfaces other than the radio access interface of whichthe HTTP session is terminated.

If there is the radio access interface receiving the streaming servicedata at the network speed less than the second threshold network speedat step 1215, the station proceeds to step 1219. The station determinesnot to receive the streaming service through a corresponding radioaccess interface at step 1219. That is, the station terminates an HTTPsession established between the corresponding radio access interface andthe server at step 1219. So, thereafter, the station receives thestreaming service data through only radio access interfaces other thanthe radio access interface of which the HTTP session is terminated.

For example, a case that a corresponding HTTP session is terminated ifit is determined not to receive a streaming service through acorresponding radio access interface has been described in FIG. 12.Further, a corresponding HTTP session is terminated and a chunk whichcorresponds to threshold streaming service data amount may becontinuously requested and received for future use for the correspondinginterface in a case that it is determined not to receive the streamingservice through the corresponding radio access interface. Here, thethreshold streaming service data amount may be set to amount suitablefor checking a keep-alive state for a corresponding HTTP session.

In a process as described in FIG. 12, in a case that use of the radioaccess interface of which the HTTP session is terminated is possibleafter reception of a corresponding segment has been completed, thestation can receive streaming service data through the radio accessinterface of which the HTTP session is terminated again. In this case,the time during which the streaming service data is received at thenetwork speed less than the first threshold network speed detected atstep 1217 is reset.

Meanwhile, FIG. 12 focuses on a description of an operation of receivinga chunk in a station, however, it will be noted that the station asdescribed above performed an operation of requesting a correspondingchunk from a server already in order for receiving the chunk asdescribed in FIG. 12.

Although FIG. 12 illustrates still another example of a stabilityguaranteeing process for a streaming service in a communication systemsupporting a plurality of radio access interfaces according to anembodiment of the present disclosure, various changes could be made toFIG. 12. For example, although shown as a series of operations, variousoperations in FIG. 12 could overlap, occur in parallel, occur in adifferent order, or occur multiple times.

Still another example of a stability guaranteeing process for astreaming service in a communication system supporting a plurality ofradio access interfaces according to an embodiment of the presentdisclosure has been described with reference to FIG. 12, and stillanother example of a stability guaranteeing process for a streamingservice in a communication system supporting a plurality of radio accessinterfaces according to an embodiment of the present disclosure will bedescribed with reference to FIG. 13.

FIG. 13 schematically illustrates still another example of a stabilityguaranteeing process for a streaming service in a communication systemsupporting a plurality of radio access interfaces according to anembodiment of the present disclosure.

Referring to FIG. 13, as described above, in a case of a streamingservice, it may be operated as an important factor affecting a servicequality to maintain a network speed corresponding to an encoding bitrate applied to a streaming service in a server. So, a station needs tocontinuously monitor whether streaming service data is normally receivedthrough each radio access interface. In FIG. 13, a station monitorsreceived signal strength of each of radio access interfaces in order tomaintain a network speed corresponding to an encoding bit rate appliedto a streaming service.

Firstly, the station monitors received signal strength of each of radioaccess networks at step 1311 and proceeds to step 1313. That is, thestation monitors the received signal strength of each of the radioaccess networks for checking whether corresponding chunks are receivedat a network speed as determined when the corresponding chunks arerequested upon receiving a segment, and proceeds to step 1313. Here, itwill be assumed that the monitor interval is maintained during presettime, e.g., 10 seconds or until a preset number of segments arereceived.

At step 1313, the station determines whether there is a radio accessinterface receiving streaming service data with received signal strengthless than the first threshold received signal strength. Here, the firstthreshold received signal strength may be set appropriate to a situationof a mobile communication system, and a detailed description of anoperation of setting the first threshold received signal strength willbe omitted herein. Further, the first threshold received signal strengthmay be set to an arbitrary value.

If there is the radio access interface receiving the streaming servicedata with the received signal strength less than the first thresholdreceived signal strength, the station proceeds to step 1315. Here, thestation requests to the server such that the station may receive aremaining part, i.e., a part to be received among a chunk which isreceiving through a radio access interface receiving the streamingservice data with the received signal strength less than the firstreceived signal strength through a radio access interface other than theradio access interface receiving the streaming service data with thereceived signal strength less than the first received signal strength.Here, the request may be performed using an HTTP range request message.

If the other radio access interface receives the streaming service dataalready, the other radio access interface may additionally establish anHTTP session with the server, and receive the remaining part of thestreaming service data, i.e., the chunk from the server through theadditionally established HTTP session at step 1321. Here, an availablebandwidth of the other radio access interface at least needs to beguaranteed such that the other radio access interface may receive theremaining part of the chunk. If the available bandwidth of the otherradio access interface is not guaranteed such that the other radioaccess interface may receive the remaining part of the chunk, theadditional HTTP session is not established.

The station determines whether there is a radio access interfacereceiving the streaming service data with the second threshold receivedsignal strength among radio access interfaces receiving the streamingservice data with the first threshold received signal strength at step1315. Here, the second threshold received signal strength may be set toa value less than the first threshold received signal strength. If thereis no radio access interface receiving the streaming service data withthe received signal strength less than the second threshold receivedsignal strength, the station proceeds to step 1317.

The station determines whether the radio access interface receiving thestreaming service data with the received signal strength less than thefirst threshold received signal strength receives the streaming servicedata with the received signal strength less than the first thresholdreceived signal strength during preset time at step 1317. If the radioaccess interface receiving the streaming service data with the receivedsignal strength less than the first threshold received signal strengthdoes not receive the streaming service data with the received signalstrength less than the first threshold received signal strength duringthe preset time, the station returns to step 1311.

If the radio access interface receiving the streaming service data withthe received signal strength less than the first threshold receivedsignal strength receives the streaming service data with the receivedsignal strength less than the first threshold received signal strengthduring the preset time, the station proceeds to step 1319. The stationdetermines not to receive the streaming service through a correspondingradio access interface at step 1319. That is, the station terminates anHTTP session established between the corresponding radio accessinterface and the server at step 1319. So, thereafter, the stationreceives the streaming service data through only radio access interfacesother than the radio access interface of which the HTTP session isterminated.

If there is the radio access interface receiving the streaming servicedata with the received signal strength less than the second thresholdreceived signal strength at step 1315, the station proceeds to step1319. The station determines not to receive the streaming servicethrough a corresponding radio access interface at step 1319. That is,the station terminates an HTTP session established between thecorresponding radio access interface and the server at step 1319. So,thereafter, the station receives the streaming service data through onlyradio access interfaces other than the radio access interface of whichthe HTTP session is terminated.

For example, a case that a corresponding HTTP session is terminated ifit is determined not to receive a streaming service through acorresponding radio access interface has been described in FIG. 13.Further, a corresponding HTTP session is terminated and a chunk whichcorresponds to threshold streaming service data amount may becontinuously requested and received for future use for the correspondinginterface in a case that it is determined not to receive the streamingservice through the corresponding radio access interface. Here, thethreshold streaming service data amount may be set to amount suitablefor checking a keep-alive state for a corresponding HTTP session.

In a process as described in FIG. 13, in a case that use of the radioaccess interface of which the HTTP session is terminated is possibleafter reception of a corresponding segment has been completed, thestation may receive streaming service data through the radio accessinterface of which the HTTP session is terminated again. In this case,the time during which the streaming service data is received with thereceived signal strength less than the first threshold received signalstrength detected at step 1317 is reset.

Meanwhile, FIG. 13 focuses on a description of an operation of receivinga chunk in a station, however, it will be noted that the station asdescribed above performed an operation of requesting a correspondingchunk from a server already in order for receiving the chunk asdescribed in FIG. 13.

Although FIG. 13 illustrates still another example of a stabilityguaranteeing process for a streaming service in a communication systemsupporting a plurality of radio access interfaces according to anembodiment of the present disclosure, various changes could be made toFIG. 13. For example, although shown as a series of operations, variousoperations in FIG. 13 could overlap, occur in parallel, occur in adifferent order, or occur multiple times.

Still another example of a stability guaranteeing process for astreaming service in a communication system supporting a plurality ofradio access interfaces according to an embodiment of the presentdisclosure has been described with reference to FIG. 13, and stillanother example of a stability guaranteeing process for a streamingservice in a communication system supporting a plurality of radio accessinterfaces according to an embodiment of the present disclosure will bedescribed with reference to FIG. 14.

FIG. 14 schematically illustrates still another example of a stabilityguaranteeing process for a streaming service in a communication systemsupporting a plurality of radio access interfaces according to anembodiment of the present disclosure.

Referring to FIG. 14, as described above, in a case of a streamingservice, it may be operated as an important factor affecting a servicequality to maintain a network speed corresponding to an encoding bitrate applied to a streaming service in a server. So, a station needs tocontinuously monitor whether streaming service data is normally receivedthrough each radio access interface. In FIG. 14, a station monitorsreceived signal strength of each of radio access interfaces in order tomaintain a network speed corresponding to an encoding bit rate appliedto a streaming service.

Firstly, the station monitors received signal strength of each of radioaccess networks at step 1411 and proceeds to step 1413. That is, thestation monitors the received signal strength of each of the radioaccess networks for checking whether corresponding chunks are receivedat a network speed as determined when the corresponding chunks arerequested upon receiving a segment, and proceeds to step 1413. Here, itwill be assumed that the monitor interval is maintained during presettime, e.g., 10 seconds or until a preset number of segments arereceived.

At step 1413, the station determines whether there is a radio accessinterface receiving streaming service data with received signal strengthless than the first threshold received signal strength. Here, the firstthreshold received signal strength may be set appropriate to a situationof a mobile communication system, and a detailed description of anoperation of setting the first threshold received signal strength willbe omitted herein. Further, the first threshold received signal strengthmay be set to an arbitrary value.

If there is the radio access interface receiving the streaming servicedata with the received signal strength less than the first thresholdreceived signal strength, the station proceeds to step 1415. Here, thestation requests to the server that the station enables to receive achunk which is receiving through a radio access interface receiving thestreaming service data with received signal strength less than the firstreceived signal strength through a radio access interface other than theradio access interface receiving the streaming service data with thereceived signal strength less than the first received signal strength.Here, the request may be performed using an HTTP range request message.

If the other radio access interface receives the streaming service dataalready, the other radio access interface may additionally establish anHTTP session with the server, and receive the streaming service data,i.e., the chunk from the server through the additionally establishedHTTP session at step 1421. Here, an available bandwidth of the otherradio access interface at least needs to be guaranteed such that theother radio access interface may receive the chunk. If the availablebandwidth of the other radio access interface is not guaranteed suchthat the other radio access interface may receive the remaining part ofthe chunk, the additional HTTP session is not established. As a result,in FIG. 14, a station receives the same chunk through a plurality ofradio access interfaces in order to guarantee stability for reception ofa streaming service. That is, the station guarantees the stability forthe reception of the streaming service by receiving a correspondingchunk through other radio access interface even though the radio accessinterface receiving the streaming service data with the first thresholdreceived signal strength receives the corresponding chunk.

The station determines whether there is a radio access interfacereceiving the streaming service data with the second threshold receivedsignal strength among radio access interfaces receiving the streamingservice data with the first threshold received signal strength at step1415. Here, the second threshold received signal strength may be set toa value less than the first threshold received signal strength. If thereis no radio access interface receiving the streaming service data withthe received signal strength less than the second threshold receivedsignal strength, the station proceeds to step 1417.

The station determines whether the radio access interface receiving thestreaming service data with the received signal strength less than thefirst threshold received signal strength receives the streaming servicedata with the received signal strength less than the first thresholdreceived signal strength during preset time at step 1417. If the radioaccess interface receiving the streaming service data with the receivedsignal strength less than the first threshold received signal strengthdoes not receive the streaming service data with the received signalstrength less than the first threshold received signal strength duringthe preset time, the station returns to step 1411.

If the radio access interface receiving the streaming service data withthe received signal strength less than the first threshold receivedsignal strength receives the streaming service data with the receivedsignal strength less than the first threshold received signal strengthduring the preset time, the station proceeds to step 1419. The stationdetermines not to receive the streaming service through a correspondingradio access interface at step 1419. That is, the station terminates anHTTP session established between the corresponding radio accessinterface and the server at step 1419. So, thereafter, the stationreceives the streaming service data through only radio access interfacesother than the radio access interface of which the HTTP session isterminated.

If there is the radio access interface receiving the streaming servicedata with the received signal strength less than the second thresholdreceived signal strength at step 1415, the station proceeds to step1419. The station determines not to receive the streaming servicethrough a corresponding radio access interface at step 1419. That is,the station terminates an HTTP session established between thecorresponding radio access interface and the server at step 1419. So,thereafter, the station receives the streaming service data through onlyradio access interfaces other than the radio access interface of whichthe HTTP session is terminated.

For example, a case that a corresponding HTTP session is terminated if astreaming service is not received through a corresponding radio accessinterface has been described in FIG. 14. Further, a corresponding HTTPsession is terminated and a chunk which corresponds to thresholdstreaming service data amount may be continuously requested and receivedfor future use for the corresponding interface in a case of determiningnot to receive the streaming service through the corresponding radioaccess interface. Here, the threshold streaming service data amount maybe set to amount suitable for checking a keep-alive state for acorresponding HTTP session.

In a process as described in FIG. 14, in a case that use of the radioaccess interface of which the HTTP session is terminated is possibleafter reception of a corresponding segment has been completed, thestation may receive streaming service data through the radio accessinterface of which the HTTP session is terminated again. In this case,the time for which the streaming service data has been received with thereceived signal strength less than the first threshold received signalstrength detected at step 1417 is reset.

Meanwhile, FIG. 14 focuses on a description of an operation of receivinga chunk in a station, however, it will be noted that the station asdescribed above performed an operation of requesting a correspondingchunk from a server already in order for receiving the chunk asdescribed in FIG. 14.

Although FIG. 14 illustrates still another example of a reliabilityguaranteeing process for a streaming service in a communication systemsupporting a plurality of radio access interfaces according to anembodiment of the present disclosure, various changes could be made toFIG. 14. For example, although shown as a series of operations, variousoperations in FIG. 14 could overlap, occur in parallel, occur in adifferent order, or occur multiple times.

Still another example of a reliability guaranteeing process for astreaming service in a communication system supporting a plurality ofradio access interfaces according to an embodiment of the presentdisclosure has been described with reference to FIG. 14, and a processof receiving streaming service data such that high-definition videocontent may be played from playback start time in a communication systemsupporting a plurality of radio access interfaces according to anembodiment of the present disclosure will be described with reference toFIGS. 15 to 17.

Firstly, a process of receiving streaming service data in a case that anHTTP AS protocol is used in a communication system supporting aplurality of radio access interfaces according to an embodiment of thepresent disclosure will be described with reference to FIG. 15.

FIG. 15 schematically illustrates a process of receiving streamingservice data in a case that an HTTP AS protocol is used in acommunication system supporting a plurality of radio access interfacesaccording to an embodiment of the present disclosure.

Referring to FIG. 15, the communication system includes a station 1511and a server 1513.

Firstly, the station 1511 transmits a play list request message torequest a play list to the server 1513 at step 1515. After receiving theplay list request message from the station 1511, the server 1513transmits a play list response message as a response message to the playlist request message to the station 1511 at step 1517. Here, the playlist response message includes a play list. Here, the play list includesa uniform resource indicator (URL) for playing corresponding videocontent and encoding bit rate information applied to the video content.For example, the play list may be expressed as the following.

<Play List>

Playback URL1, Bitrate=100 kbps (low)

Playback URL2, Bitrate=400 kbps (medium)

Playback URL3, Bitrate=1.2 Mbps (high)

In the play list, Playback URL indicates a URL for video content, andBitrate indicates an encoding bit rate information applied to the videocontent.

After receiving the play list response message from the server 1513, thestation 1511 selects the lowest URL, i.e., a URL 1 which corresponds toan encoding bit rate applied to video content since the station 1511does not initially have bandwidth information for a used network, andtransmits a message, e.g., an HTTP range message to request to transmitthe first segment to the server 1513 based on information of the URL1 atstep 1519.

After receiving the HTTP range message to request to transmit the firstsegment from the station 1511, the server 1513 transmits the firstsegment which corresponds to the URL1 to the station 1511 at step 1521.After receiving the first segment from the server 1513, the station 1511measures a bandwidth while receiving the first segment at step 1523.

So, if the station 1511 transmits an HTTP range message to request tothe next segment, i.e., the second segment, the station 1511 selects aURL from the play list based on the measured bandwidth. For example, thebandwidth measured by the station 1511 is 500 kbps, the station 1511selects a URL2. Then, the station 1511 transmits a message, e.g., anHTTP range message to request to transmit the second segment to theserver 1513 based on information of the selected URL2 at step 1525.Until a termination request for playback of corresponding video contentis detected, an operation corresponding to steps 1523 and 1525 isrepetitively performed.

If a Wi-Fi interface and LTE interface are connected at the same time,and a bandwidth of the Wi-Fi interface is relatively low, for example,the bandwidth of the Wi-Fi interface is 500 Kbps less than a thresholdbandwidth, a station plays low-definition video content through theWi-Fi interface even though the station may watch high-definition videocontent through the LTE interface. That is, a bandwidth of the Wi-Fiinterface is 500 Kbps, so it is inevitable that the station always playsvideo content of 400 Kbps.

So, an embodiment of the present disclosure proposes a scheme ofrequesting to transit a corresponding segment using an LTE interfaceuntil an encoding bit rate applied to video content of the correspondingsegment becomes a maximum bit rate if an encoding bit rate applied tovideo content of a segment for which transmission is currently requestedis not the highest bit rate and receiving the corresponding segmentbased on the request. Here, the highest bit rate may be adaptively setaccording to a situation of a communication system which uses aplurality of radio access interfaces.

A process of receiving streaming service data such that high-definitionvideo content may be played from playback start time in a mobilecommunication system supporting a plurality of radio access interfacesaccording to an embodiment of the present disclosure will be describedwith reference to FIGS. 16a and 16 b.

FIGS. 16a and 16b schematically illustrate a process of receivingstreaming service data such that high-definition video content may beplayed from playback start time in a mobile communication systemsupporting a plurality of radio access interfaces according to anembodiment of the present disclosure.

Referring to FIGS. 16a and 16b , a station transmits a play list requestmessage to a server and receives a play list response message from theserver at step 1611, and proceeds to step 1613. The station selects aURL mapped to the lowest encoding bit rate applied to video content in aplay list received through the play list response message for playingthe first segment at step 1613, and proceeds to step 1615. The stationtransmits an HTTP range message to request to transmit the first segmentthrough a Wi-Fi interface to the server, and receives the first segmentfrom the server at step 1615, and proceeds to step 1617. Here, if abandwidth of the Wi-Fi interface becomes greater than the encoding bitrate applied to the video content of the segment, the station sets astate to a SINGLE_WIFI state on which only a Wi-Fi interface is used.

Meanwhile, the station measures a bandwidth based on the received firstsegment at step 1617, and proceeds to step 1619. A process of measuringa bandwidth will be described with reference to FIG. 17, so a detaileddescription thereof will be omitted herein. The station selects a URLfrom the play list based on the bandwidth measurement result at step1619, and proceeds to step 1621.

The station determines whether the state of the station is set to theSINGLE_WIFI state at step 1621. If the state is set to the SINGLE_WIFIstate, the station proceeds to step 1623. The station determines whetheran encoding bit rate applied to video content which corresponds to theselected URL is less than a maximum bit rate at step 1623. If theencoding bit rate applied to the video content which corresponds to theselected URL is not less than the maximum bit rate, that is, if theencoding bit rate applied to the video content which corresponds to theselected URL is greater than or equal to the maximum bit rate, thestation proceeds to step 1625. The station sets the state to theSINGLE_WIFI state, transmits an HTTP range message to request totransmit the second segment to the server through the Wi-Fi interface,and receives the second segment from the server at step 1625, andproceeds to step 1635. The station determines whether a video contentplayback termination request is detected at step 1635. If the videocontent playback termination request is not detected, the stationreturns to step 1617.

If the encoding bit rate applied to the video content which correspondsto the selected URL is less than the maximum bit rate at step 1623, thestation proceeds to step 1631. The station sets the state to aSINGLE_LTE state as a state on which only an LTE interface is used,transmits an HTTP range message to request to transmit the secondsegment to the server through the LTE interface, and receives the secondsegment from the server at step 1631, and proceeds to step 1635.

Meanwhile, if the state is not set to the SINGLE_WIFI state at step1621, the station proceeds to step 1627. The station determines whetherthe state is set to the SINGLE_LTE sate at step 1627. If the state isset to the SINGLE_LTE sate, the station proceeds to step 1629. Thestation determines whether an encoding bit rate applied to video contentwhich corresponds to the selected URL is less than a maximum bit rate atstep 1629. If the encoding bit rate applied to the video content whichcorresponds to the selected URL is less than the maximum bit rate, thestation proceeds to step 1631. If the state is not set to the SINGLE_LTEstate at step 1627, the station proceeds to step 1633. The station setsthe state to a TWO_CHUNK state on which two radio access interfaces,i.e., both the Wi-Fi interface and the LTE interface are used, transmitsan HTTP range message to request to transmit the second segment to theserver through the Wi-Fi interface and the LTE interface, and receivesthe second segment from the server at step 1633, and proceeds to step1635.

Although FIGS. 16a and 16b illustrate a process of receiving streamingservice data such that high-definition video content may be played fromplayback start time in a mobile communication system supporting aplurality of radio access interfaces according to an embodiment of thepresent disclosure, various changes could be made to FIGS. 16a and 16b .For example, although shown as a series of operations, variousoperations in FIGS. 16a and 16b could overlap, occur in parallel, occurin a different order, or occur multiple times.

A process of receiving streaming service data such that high-definitionvideo content may be played from playback start time in a mobilecommunication system supporting a plurality of radio access interfacesaccording to an embodiment of the present disclosure has been describedwith reference to FIGS. 16a and 16b , and a process of measuring abandwidth shown in step 1617 in FIG. 16a will be described withreference to FIG. 17.

FIG. 17 schematically illustrates a process of measuring a bandwidthshown in step 1617 in FIG. 16 a.

Referring to FIG. 17, a station determines whether a state of thestation is set to a SINGLE_WIFI state at step 1711. If the state is setto the SINGLE_WIFI state, the station proceeds to step 1713. The stationmeasures a bandwidth for a Wi-Fi interface at step 1713.

If the state is not set to the SINGLE_WIFI state at step 1711, thestation proceeds to step 1715. The station determines whether a state ofthe station is set to a SINGLE_LTE state at step 1715. If the state isset to the SINGLE_LTE state, the station proceeds to step 1717. Thestation measures a bandwidth for an LTE interface at step 1717.

If the state is not set to the SINGLE_LTE state at step 1715, thestation proceeds to step 1719. The station measures a bandwidth for eachof the Wi-Fi interface and the LTE interface at step 1719 and proceedsto step 1721. The station determines whether the bandwidth of the Wi-Fiinterface is greater than an encoding bit rate applied to correspondingvideo content at step 1721. If the bandwidth of the Wi-Fi interface isgreater than the encoding bit rate applied to corresponding videocontent, the station proceeds to step 1723. The station sets the stateto the SINGLE_WIFI state at step 1723.

Although FIG. 17 illustrates a process of measuring a bandwidth shown instep 1617 in FIG. 16a , various changes could be made to FIG. 17. Forexample, although shown as a series of operations, various operations inFIG. 17 could overlap, occur in parallel, occur in a different order, oroccur multiple times.

A process of measuring a bandwidth shown in step 1617 in FIG. 16a hasbeen described with reference to FIG. 17, and an inner structure of aserver in a communication system supporting a plurality of radio accessinterfaces according to an embodiment of the present disclosure will bedescribed with reference to FIG. 18.

FIG. 18 schematically illustrates an inner structure of a server in acommunication system supporting a plurality of radio access interfacesaccording to an embodiment of the present disclosure.

Referring to FIG. 18, a server 1800 includes a transmitter 1811, acontroller 1813, a receiver 1815, and a storage unit 1817.

The controller 1813 controls the overall operation of the server 1800.The controller 1813 controls the server 1800 to perform a streamingservice providing operation, i.e., an overall operation related to anoperation of providing a streaming service to a station supporting aplurality of radio access interfaces according to an embodiment of thepresent disclosure. Here, the operation of providing the streamingservice to the station supporting the plurality of radio accessinterfaces according to an embodiment of the present disclosure has beendescribed with FIGS. 1 to 17, and a detailed description thereof will beomitted herein.

The transmitter 1811 transmits various signals and various messages to astation and the like under a control of the controller 1813. The varioussignals and various messages transmitted in the transmitter 1811 havebeen described with reference to FIGS. 1 to 17, and a detaileddescription thereof will be omitted herein.

The receiver 1815 receives various signals and various messages from thestation and the like under a control of the controller 1813. The varioussignals and various messages received in the receiver 1815 have beendescribed with reference to FIGS. 1 to 17, and a detailed descriptionthereof will be omitted herein.

The storage unit 1817 stores various programs, various data, and thelike necessary for an operation of the server 1800, and more particular,information related to an operation of providing a streaming service toa station supporting a plurality of radio access interfaces according toan embodiment of the present disclosure and the like. The storage unit1817 stores various signals and various messages which are received bythe receiver 1815 from the station and the like.

While the transmitter 1811, the controller 1813, the receiver 1815, andthe storage unit 1817 are described in the server 1800 as separateunits, however, the server 1800 may be implemented as a form that atleast two of the transmitter 1811, the controller 1813, the receiver1815, and the storage unit 1817 may be incorporated into a single unit.

An inner structure of a server in a communication system supporting aplurality of radio access interfaces according to an embodiment of thepresent disclosure has been described with reference to FIG. 18, and aninner structure of a station in a communication system supporting aplurality of radio access interfaces according to an embodiment of thepresent disclosure will be described with reference to FIG. 19.

FIG. 19 schematically illustrates an inner structure of a station in acommunication system supporting a plurality of radio access interfacesaccording to an embodiment of the present disclosure.

Referring to FIG. 19, a station 1900 includes a transmitter 1911, acontroller 1913, a receiver 1915, and a storage unit 1917.

The controller 1913 controls the overall operation of the station 1900.The controller 1913 controls the station 1900 to perform a streamingservice providing operation, i.e., an overall operation related to anoperation of providing a streaming service to a station supporting aplurality of radio access interfaces according to an embodiment of thepresent disclosure. Here, the operation of providing the streamingservice to the station supporting the plurality of radio accessinterfaces according to an embodiment of the present disclosure has beendescribed with FIGS. 1 to 17, and a detailed description thereof will beomitted herein.

The transmitter 1911 transmits various signals and various messages to aserver and the like under a control of the controller 1913. The varioussignals and various messages transmitted in the transmitter 1911 havebeen described with reference to FIGS. 1 to 17, and a detaileddescription thereof will be omitted herein. Further, an inner structureof the transmitter 1911 will be described with reference to FIG. 20, anda detailed description thereof will be omitted herein.

The receiver 1915 receives various signals and various messages from theserver and the like under a control of the controller 1913. The varioussignals and various messages received in the receiver 1915 have beendescribed with reference to FIGS. 1 to 17, and a detailed descriptionthereof will be omitted herein.

The storage unit 1917 stores various programs, various data, and thelike necessary for an operation of the station 1900, and moreparticular, information related to an operation of providing a streamingservice to a station supporting a plurality of radio access interfacesaccording to an embodiment of the present disclosure and the like. Thestorage unit 1917 stores various signals and various messages which arereceived by the receiver 1915 from the server and the like.

While the transmitter 1911, the controller 1913, the receiver 1915, andthe storage unit 1917 are described in the station 1900 as separateunits, however, the station 1900 may be implemented as a form that atleast two of the transmitter 1911, the controller 1913, the receiver1915, and the storage unit 1917 may be incorporated into a single unit.An inner structure of a station in a communication system supporting aplurality of radio access interfaces according to an embodiment of thepresent disclosure has been described with reference to FIG. 19, and aninner structure of a transmitter 1911 in FIG. 19 will be described withreference to FIG. 20.

FIG. 20 schematically illustrates an inner structure of a transmitter1911 in FIG. 19.

Referring to FIG. 20, the transmitter 1911 includes a plurality of radioaccess interfaces, e.g., N radio access interfaces, i.e., a radio accessinterface #1 2011-1, a radio access interface #2 2011-2, . . . , a radioaccess interface #N 2011-N. Here, one of the radio access interface #12011-1, the radio access interface #2 2011-2, . . . , the radio accessinterface #N 2011-N may be a Wi-Fi interface, and another one may be anLTE interface.

While the radio access interface #1 2011-1, the radio access interface#2 2011-2, . . . , the radio access interface #N 2011-N are described inthe transmitter 1911 as separate units, however, the transmitter 1911may be implemented as a form that at least two of the radio accessinterface #1 2011-1, the radio access interface #2 2011-2, . . . , theradio access interface #N 2011-N may be incorporated into a single unit.

An inner structure of a transmitter 1911 in FIG. 19 has been describedwith reference to FIG. 20, and an inner structure of a receiver 1915 inFIG. 19 will be described with reference to FIG. 21.

FIG. 21 schematically illustrates an inner structure of a receiver 1915in FIG. 19.

Referring to FIG. 21, the receiver 1915 includes a plurality of radioaccess interfaces, e.g., N radio access interfaces, i.e., a radio accessinterface #1 2111-1, a radio access interface #2 2111-2, . . . , a radioaccess interface #N 2111-N. Here, one of the radio access interface #12111-1, the radio access interface #2 2111-2, . . . , the radio accessinterface #N 2111-N may be a Wi-Fi interface, and another one may be anLTE interface.

While the radio access interface #1 2111-1, the radio access interface#2 2111-2, . . . , the radio access interface #N 2111-N are described inthe receiver 1915 as separate units, however, the receiver 1915 may beimplemented as a form that at least two of the radio access interface #12111-1, the radio access interface #2 2111-2, . . . , the radio accessinterface #N 2111-N may be incorporated into a single unit.

As is apparent from the foregoing description, an embodiment of thepresent disclosure enables to receive streaming service data in a mobilecommunication system supporting a plurality of radio access interfaces.

An embodiment of the present disclosure enables to seamlessly receivestreaming service data in a mobile communication system supporting aplurality of radio access interfaces

An embodiment of the present disclosure enables to receive streamingservice data corresponding to an encoding bit rate applied to streamingservice content in a mobile communication system supporting a pluralityof radio access interfaces

An embodiment of the present disclosure enables to receive streamingservice data by considering load balancing in a mobile communicationsystem supporting a plurality of radio access interfaces.

An embodiment of the present disclosure enables to receive streamingservice data such that high-definition video content may be played fromplayback start time in a mobile communication system supporting aplurality of radio access interfaces according to an embodiment of thepresent disclosure.

An embodiment of the present disclosure enables to receive streamingservice data by considering guarantee of stability in a mobilecommunication system supporting a plurality of radio access interfaces.

Certain aspects of the present disclosure may also be embodied ascomputer readable code on a non-transitory computer readable recordingmedium. A non-transitory computer readable recording medium is any datastorage device that can store data, which can be thereafter read by acomputer system. Examples of the non-transitory computer readablerecording medium include read only memory (ROM), random access memory(RAM), CD-ROMs, magnetic tapes, floppy disks, optical data storagedevices, and carrier waves (such as data transmission through theInternet).The non-transitory computer readable recording medium can alsobe distributed over network coupled computer systems so that thecomputer readable code is stored and executed in a distributed fashion.In addition, functional programs, code, and code segments foraccomplishing the present disclosure can be easily construed byprogrammers skilled in the art to which the present disclosure pertains.

It can be appreciated that a method and apparatus according to anembodiment of the present disclosure may be implemented by hardware,software and/or a combination thereof. The software may be stored in anon-volatile storage, for example, an erasable or re-writable ROM, amemory, for example, a RAM, a memory chip, a memory device, or a memoryintegrated circuit (IC), or an optically or magnetically recordablenon-transitory machine-readable (e.g., computer-readable), storagemedium (e.g., a compact disk (CD), a digital video disc (DVD), amagnetic disk, a magnetic tape, and/or the like).A method and apparatusaccording to an embodiment of the present disclosure may be implementedby a computer or a mobile terminal that includes a controller and amemory, and the memory may be an example of a non-transitorymachine-readable (e.g., computer-readable), storage medium suitable tostore a program or programs including instructions for implementingvarious embodiments of the present disclosure.

The present disclosure may include a program including code forimplementing the apparatus and method as defined by the appended claims,and a non-transitory machine-readable (e.g., computer-readable), storagemedium storing the program. The program may be electronicallytransferred via any media, such as communication signals, which aretransmitted through wired and/or wireless connections, and the presentdisclosure may include their equivalents.

An apparatus according to an embodiment of the present disclosure mayreceive the program from a program providing device which is connectedto the apparatus via a wire or a wireless and store the program. Theprogram providing device may include a memory for storing instructionswhich instruct to perform a content protect method which has beenalready installed, information necessary for the content protect method,and the like, a communication unit for performing a wired or a wirelesscommunication with a graphic processing device, and a controller fortransmitting a related program to a transmitting/receiving device basedon a request of the graphic processing device or automaticallytransmitting the related program to the transmitting/receiving device.

While the present disclosure has been shown and described with referenceto various embodiments thereof, it will be understood by those skilledin the art that various changes in form and details may be made thereinwithout departing from the spirit and scope of the present disclosure asdefined by the appended claims and their equivalents.

1. A method of a station in a mobile communication system, the methodcomprising: receiving streaming service data through at least one of aradio access interfaces, wherein the at least one radio access interfaceis selected based on a network speed which corresponds to an encodingbit rate applied to the streaming service at which the streaming servicedata is to be received.
 2. The method of claim 1, wherein the at leastone interface is determined based on at least one of a primary radioaccess interface, a network speed of each of the radio accessinterfaces, a load balancing for the radio access interfaces, and aguarantee of stability for the radio access interfaces.
 3. (canceled) 4.(canceled)
 5. (canceled)
 6. The method of claim 1, further comprising:if the at least one radio access interface includes at least two radioaccess interfaces, monitoring the at least two radio access interfaces;and if there is a radio access interface of which a network speed isless than a threshold network speed among the at least two radio accessinterfaces, controlling to receive a part of streaming service datareceived through the radio access interface through a radio accessinterface other than the radio access interface.
 7. The method of claim1, further comprising: if the at least one radio access interfaceincludes at least two radio access interfaces, monitoring the at leasttwo radio access interfaces; and if there is a radio access interface ofwhich received signal strength is less than threshold received signalstrength among the at least two radio access interfaces, controlling toreceive a part of streaming service data received through the radioaccess interface through a radio access interface other than the radioaccess interface.
 8. The method of claim 1, further comprising: if theat least one radio access interface includes at least two radio accessinterfaces, monitoring the at least two radio access interfaces; ifthere is at least one first radio access interface of which a networkspeed is less than a first threshold network speed among the at leasttwo radio access interfaces and there is at least one second radioaccess interface of which a network speed is less than a secondthreshold network speed among the at least one first radio accessinterface, determining not to receive streaming service data through theat least one second radio access interface; and if there is no secondradio access interface and the at least one first radio access receivesstreaming service data at the network speed less than the firstthreshold network speed during preset time, determining not to receivestreaming service data through the at least one first radio accessinterface.
 9. The method of claim 8, further comprising: if there is theat least one first radio access interface, receiving a part of thestreaming service data which is being received through a remaining radioaccess interface among the at least two radio access interfaces.
 10. Themethod of claim 8, further comprising: if there is the at least onefirst radio access interface, receiving the streaming service data whichis being received through a remaining radio access interface among theat least two radio access interfaces.
 11. The method of claim 1, furthercomprising: if the at least one radio access interface includes at leasttwo radio access interfaces, monitoring the at least two radio accessinterfaces; and if there is at least one radio access interface of whichreceived signal strength is less than first threshold received signalstrength among the at least two radio access interfaces and there is atleast one second radio access interface of which received signalstrength is less than second received signal strength among the at leastone first radio access interface, determining not to receive streamingservice data through the at least one second radio access interface; andif there is no second radio access interface and the at least one firstradio access interface receives streaming service data at the receivedsignal strength less than the first threshold received signal strengthduring preset time, determining not to receive streaming service datathrough the at least one first radio access interface.
 12. The method ofclaim 11, further comprising: if there is the at least one first radioaccess interface, receiving a part of the streaming service data whichis being received through a remaining radio access interface among theat least two radio access interfaces.
 13. The method of claim 11,further comprising: if there is the at least one first radio accessinterface, receiving the streaming service data which is being receivedthrough a remaining radio access interface among the at least two radioaccess interfaces.
 14. A station in a mobile communication system, thestation comprising: a receiver for receiving streaming service datathrough at least one of radio access interfaces, wherein the at leastone radio access interface is selected based on a network speed whichcorresponds to an encoding bit rate applied to the streaming service atwhich the streaming service data is to be received.
 15. The station ofclaim 14, wherein the at least one radio access interface is determinedbased on at least one of a primary radio access interface, a networkspeed of each of the radio access interfaces, a load balancing for theradio access interfaces, and a guarantee of stability for the radioaccess interfaces.
 16. (canceled)
 17. (canceled)
 18. (canceled)
 19. Thestation of claim 14, further comprising: a controller, if the at leastone radio access interface includes at least two radio accessinterfaces, the receiver monitors the at least two radio accessinterfaces, and if there is a radio access interface of which a networkspeed is less than a threshold network speed among the at least tworadio access interfaces, the controller controls to receive a part ofstreaming service data received through the radio access interfacethrough a radio access interface other than the radio access interface.20. The station of claim 14, further comprising: a controller, if the atleast one radio access interface includes at least two radio accessinterfaces, the receiver monitors the at least two radio accessinterfaces, and if there is a radio access interface of which receivedsignal strength is less than threshold received signal strength amongthe at least two radio access interfaces, the controller controls toreceive a part of streaming service data received through the radioaccess interface through a radio access interface other than the radioaccess interface.
 21. The station of claim 14, further comprising: acontroller, if the at least radio access interface includes at least tworadio access interfaces, the receiver monitors the at least two radioaccess interfaces, if there is at least one first radio access interfaceof which a network speed is less than a first threshold network speedamong the at least two radio access interfaces and there is at least onesecond radio access interface of which a network speed is less than asecond threshold network speed among the at least one first radio accessinterface, the controller determines not to receive streaming servicedata through the at least one second radio access interface, and ifthere is no second radio access interface and the at least one firstradio access receives streaming service data at the network speed lessthan the first threshold network speed during preset time, thecontroller determines not to receive streaming service data through theat least one first radio access interface.
 22. The station of claim 21,wherein, if there is the at least one first radio access interface, thereceiver receives a part of the streaming service data which is beingreceived through a remaining radio access interface among the at leasttwo radio access interfaces.
 23. The station of claim 21, wherein, ifthere is the at least one first radio access interface, the receiverreceives the streaming service data which is being received through aremaining radio access interface among the at least two radio accessinterfaces.
 24. The station of claim 14, further comprising: acontroller, if the at least one radio access interface includes at leasttwo radio access interfaces, the receiver monitors the at least tworadio access interfaces, if there is at least one radio access interfaceof which received signal strength is less than first threshold receivedsignal strength among the at least two radio access interfaces and thereis at least one second radio access interface of which received signalstrength is less than second received signal strength among the at leastone first radio access interface, the controller determines not toreceive streaming service data through the at least one second radioaccess interface, and if there is no second radio access interface andthe at least one first radio access interface receives streaming servicedata at the received signal strength less than the first thresholdreceived signal strength during preset time, the controller determinesnot to receive streaming service data through the at least one firstradio access interface.
 25. The station of claim 24, wherein, if thereis the at least one first radio access interface, the receiver receivesa part of the streaming service data which is being received through aremaining radio access interface among the at least two radio accessinterfaces.
 26. The station of claim 24, wherein, if there is the atleast one first radio access interface, the receiver receives thestreaming service data which is being received through a remaining radioaccess interface among the at least two radio access interfaces.